Maybe not fix it, but prevent that app from committing further actions attributed to your device. 

You think changing the passwords would fix it?

Change the password for all the affected accounts, to be sure to stop the abuse, then hope that the ban is only temporary... 

So I made the idiot mistake yesterday of trying out one of those apps that gets you likes (pretty cringe, I know) and made a seperate account for it. Well, Instagram detected that and I think they IP banned my phone. I can't create or log into any account on it but my account works on every other device. Anything I can do at this point to get it working on my phone? Thanks in advance for any help

Locked out of Instagram on phone