wifi issues

on my iphone 13 mini running ios15.4 has problems with internet. whenever i connect to a wifi source (my home router), it says im connected and the wifi symbol shows up in the corner with full bars for about a split second, then disappears. when i check to see whats up in settings, it says i am connected perfectly. this hasnt only happened with my router, so i know it isnt a problem with that. i tried hooking up to my partners hotspot and the same thing happened. i have reset my connection settings multiple times and it still isnt working. any fixes in mind?