Lighting broken and everything blurry when looking in certain directions

Hello, we have a relatively big level and the light does very odd things sometimes. This depends on shifting the view around, and if it hits a certain angle everything blurs weirdly, like in the images attached. At some point everything was flickering wildly, also only in certain angles, but this is currently not the case. If anyone by any chance has experienced similiar looking effects and found a fix I would greatly appreciate it! I obviously can provide more infos about the level but I don’t quite know where to start.
Thank you!
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