I don’t do ANYTHING on twitter other than occasionally click on a post by a local sports guy when I get a notification. Literally EVERYTHING else in my feed is right wing political non-sense. The extent of my interactions were hitting block early on, and when I realized that did nothing to give their “algorithm” a clue that I wasn’t interested I just started ignoring it entirely.

If it’s still under warranty, they HAVE to unless they can prove your modification caused the system to fail. It’s no different than the silly stickers that say “warranty void if removed” - that’s a nice fantasy for the manufacturer, but at least in the US it’s been ruled those stickers mean absolutely nothing. If they’re refusing to fix a phone under warranty, contact your local AG and enjoy watching them squirm. Loop in the FTC for good measure.

https://www.ftc.gov/business-guidance/resources/businesspersons-guide-federal-warranty-law#Magnuson-Moss