Facebook Messenger connection forces me to select an Instagram account

The reason Continue is greyed out is that the app is asking for Instagram permissions in the same request as the Page permissions. Meta's picker will not let you past that screen until you have selected at least one asset of every type being requested. It isn't a ManyChat setting you can turn off, it is Meta's login dialog.

The part you can change is why that Instagram account is showing up at all. It's there because it's attached to something you selected. Two places to look:

Your Business Portfolio. If the client's Instagram account sits inside "L'encre virtuelle", every login that includes that portfolio will surface it. Business Settings, Accounts, Instagram accounts. If it's listed there and it isn't yours, remove it.

Your Page. Page settings, Linked accounts. If the client's Instagram is linked to L'Encre Virtuelle, unlink it.

If it's gone from both and the picker still shows it, that's worth a support ticket, because at that point it's stale data on Meta's side and nothing you do in ManyChat will move it.

Worth saying plainly: this is Meta's dialog, not a ManyChat limitation. Most tools that automate both Instagram and Facebook request the same permission set and will show you the same screen.

Thanks for your help.

I checked both places you mentioned.

In my “L’encre virtuelle” Business Portfolio, there are no Instagram accounts at all. I also checked my L’Encre Virtuelle Facebook Page under Linked Accounts, and it says that no Instagram account is connected.

I tried the ManyChat connection again after checking this, but Meta still displays an Instagram account and the Continue button remains greyed out until I select one.

So it looks like this may be stale data on Meta’s side, as you suggested. What would you recommend as the next step? Should I contact Meta Support, or is there anything else I should check first?

That rules out stale data, so here's what's actually happening.

Meta's login is all or nothing. Their own docs say every permission the app requests has to be granted or the app gets none of them. ManyChat's Messenger connection requests Instagram permissions alongside the Page ones, so the dialog won't let you continue until you've handed it an Instagram account. That's why Continue stays grey.

Worth knowing that the asset list is set by the app developer, not by Meta. ManyChat chose to bundle Instagram into that connection, and they could publish a Messenger-only configuration that doesn't ask for it. You can't change that from your side, so that's the specific thing to put in a support ticket. Meta Support can't help you here, nothing is broken.

As for where that Instagram account is coming from, it isn't your portfolio since you've emptied it. It's reaching the dialog through access you hold somewhere else, most likely you're a user or partner on your client's Business Portfolio. Check Business Settings and see which portfolios you belong to besides your own.

If you need this working today rather than waiting on support, the workaround is to give yourself an Instagram to select that isn't your client's. Create an Instagram professional account for L'Encre Virtuelle, link it to the Page, and pick that one. Your client's account never gets granted and you never have to use the new one.

Thank you so much for your help. It was really valuable, and I really appreciate you taking the time to explain everything so clearly.

I’m going to follow your advice and create an Instagram account for L’Encre Virtuelle to work around the issue.

Thanks again for your time and help!

Happy to help. If you hit anything else with this, or with Meta connections generally, feel free to DM me. Always glad to take a look.

Good luck with the client work.