Talk is a private messenger with voice and video calls for a small group, on a server you run.
Ask a friend who uses Talk for an invite link, open it on your iPhone, and pick a name and passphrase. To run your own server, deploy it on Railway from github.com/Princeu3/talk.
Allow notifications for Talk, and check that Focus or Do Not Disturb isn't silencing it.
Open an issue at github.com/Princeu3/talk/issues. To report a person, open the chat, tap their name and choose Report.