Allow Adalo app and microsoft teams and Slack integration

Hello everyone

Without going into too much details, I created a little saas that allows businesses to create a record, I want that record to be posted to Microsoft teams to the designated team member chat window directly.
Example: I m writing to John Doe to let him know that he is to meet with Mike tomorrow, while I m doing this in the Adalo web app, I want it to automatically post the same message to John in a chat in Microsoft teams.

So I selected custom action, ingetrations and chose zapier to do so, but how will I ensure that any company that signs up, can actually do the same without me having to setup anything in the back end, I know it will give them a pop up to login it to their 365 account, but will it work?
if you have done this before, pls walk me through, much appreciated, for teams and slack if possible.
Thanks

Update: I m aware there is a slack integration, but say different companies sign up to my saas, and they want to once they post a feedback, it sends it as a direct message to the user on teams and slacks, using their email address to find them. I created both zaps, both give error message so i m not sure how to go about it:

I m sorry to tag you, but you are the most efficient Adalo expert, would love your help on this @theadaloguy

This should all be possible. I’ve worked with Slack a bit but not Microsoft Teams. It might be a bit hard to advise without doing a live call or something. With regards to the error message, do you see the inputs passed correctly from Adalo?