Yes. Instagram lets more than one tool hold an authorisation on the same account at the same time, and connecting a second one does not disconnect the first. Nothing is revoked and nothing needs uninstalling. The trouble is not connection. It is overlap, and what goes wrong when two tools watch the same post depends entirely on which trigger fired.
That distinction is the whole answer, and almost nobody selling you a tool will explain it, because both of the tools involved would rather you just moved.
Connecting a second tool changes nothing about the first
Each tool holds its own authorisation from Instagram, granted separately, and they do not overwrite each other. When you connect a new tool, Instagram asks you to approve that one. Your existing tool keeps its own approval, keeps its automations, and keeps running.
So a trial does not require a leap. You can connect a new tool, build one automation in it, and watch what happens while everything you already had stays live. When you want the old one gone you remove its access from Instagram yourself, deliberately, at a moment you choose.
This is also why "just try it for a week" is honest advice in this category and not a trap. The reversible part is genuinely reversible.
What happens when both tools watch the same post
Here is the part that surprises people. Two tools reacting to the same post do not behave the same way. It depends on whether the thing that triggered them was a comment or a message, and the two cases fail in opposite directions.
A comment: one tool wins and the other goes quiet. When somebody comments, both tools see it and both try to answer. Instagram permits exactly one of those answers to land. Meta's Private Replies documentation is explicit that only one message may be sent to a commenter for a given comment. So the fan gets one DM, not two. The second tool's attempt is refused, and depending on the product you may never be told. The automation is not broken, it is not paused, and its dashboard may happily show it as live.
A story reply or a direct message: both tools send, and the fan gets two. A message is different from a comment. When somebody sends you a DM or replies to a story, they open a 24 hour messaging window, and inside that window a tool may send freely. There is no one-per-conversation rule to stop the second one. Both tools answer, the fan receives two DMs from you within seconds of each other, and the account that looks careless is yours.
So the same overlap produces a silent failure on one trigger and a visible embarrassment on the other. If you take one thing from this page, take that.
Why a comment and a message behave differently
A comment is not a conversation. It buys a single reply into somebody's inbox and nothing more, which is why Instagram caps it at one, and why the cap is per comment rather than per tool or per day.
A message is a conversation. The person wrote to you, so Instagram treats the door as open and lets you answer as often as the next 24 hours allow. The generosity that makes story replies useful is the same generosity that lets two tools both walk through the door.
Neither rule is anybody's product decision. They are the platform's, they are identical for every tool on Instagram's official API, and no product has a route around them.
How to run both without either of these happening
One rule covers it: never let two tools watch the same post.
Give the new tool new posts. The cleanest way to trial anything. Build in the new tool on posts you publish from today, leave the old tool on everything already live, and let the two estates stay separate until you have decided. Nothing collides because nothing overlaps.
Or move one post at a time. Rebuild a single automation in the new tool, and pause its twin in the old one before the new version goes live, not after. The order matters. Paused first, live second, and for a few seconds nobody is answering, which is a far better failure than two tools both answering.
Watch the story reply and DM keyword automations hardest. These are the ones that double up, and they are easy to forget because they are not attached to a post you can look at. If you have a welcome message or a story keyword running in the old tool, that is the first thing to switch off.
Do not split by keyword and assume it holds. Two different keywords on the same post look safe and mostly are, until somebody types both words in one comment, or types the word your other tool is watching for. Separating by post is reliable. Separating by keyword inside a post is a guess about what people will type.
What running two tools costs you
Four things, and only one of them is money.
You pay both. Obvious, and worth saying anyway, because a trial that quietly runs for four months is a bill nobody decided to approve.
They share one sending budget. Instagram's own sending limits are counted against the account rather than against each tool. Two tools do not get an allowance each. They spend the same one, neither can see what the other has used, and a busy day can run it down faster than either dashboard suggests. This matters most in the hours after a post does unusually well, which is the moment you were relying on both of them.
Your history does not move. Contacts, conversations and link click numbers belong to the tool that collected them. A new tool starts empty, and the old tool's record stops the day you stop using it. Export anything you want to keep while you still have access.
Your measurement gets harder before it gets easier. With two tools running, neither one can tell you what your account did. Each sees its own half. This is the real argument for keeping the trial short and the split clean, rather than running a comfortable hybrid for a season.
Where this stops being true
This page is about tools on Instagram's official API, the ones you connect through Instagram's own login screen. Tools that ask for your Instagram password and log in as you are a different situation, and running one of those alongside anything else compounds a risk you should not be taking in the first place. The account carrying that risk is yours, not theirs.
We cannot tell you which tool wins a comment. We can tell you that Instagram permits one reply and that one of them will lose. Which one is decided by whose attempt arrives first, and that is not something either tool controls or publishes. If you need a specific tool to answer a specific post, the answer is to make sure it is the only one watching that post, not to work out the race.
And this is Instagram only. Other platforms do not share these rules, and a habit learned here does not transfer.
The short version: two tools on one account is a normal, safe way to try something, right up until both of them are pointed at the same post. Keep them apart and the overlap problem never exists.