Spot above the tank causing glitches

Hello,
what is this weird spot above my tanks that are causing graphical glitches. I found it on the new China PGZ-88 but also above PLZ05?

Looks like I can’t edit my post so here is the picture link.

https://i.ibb.co/zpFJqjr/shot-2026-07-03-17-33-16.png