What kind of ban is it?
Open the Umingle chat app: if you see a temporary notice with a timeframe, wait it out. If every session is blocked with no timeframe, or the block survives reinstalls, you are likely device-banned. Knowing which one saves you from wasting effort on the wrong fix.
What triggers bans
Nudity, sexual content, harassment, hate speech, spam, and underage use are the fast track. Less obvious triggers include pointing the camera at non-live content and mass false-reporting other users. The rules guide lists them all; most banned users broke one knowingly.
What you can actually do
For temporary bans: wait, then return with clean behavior. For permanent bans: there is no trick worth recommending, and most "unban" advice online is fiction. If you believe the ban was a mistake, the honest route is contacting the service and stating your case plainly, once. Then move on.
Staying unbanned
Keep your camera on yourself and live, keep it clean, and use the report button instead of retaliating when others misbehave. Retaliation gets both sides banned. The users who never see a ban screen are boring in exactly the right way.

