Cant Upload Image due to Internal Server Error

Hi there, We have a Problem uploading Profile pictures due to an Internal Server Error. We have created an User-account you can try it for yourself.
When we Try to Upload an Image (Profile Pic) it is showing an red area giving this message as output: Internal Server Area

we already tried to find a solution but nothing works.

pls help us with your Plugin

best regards,
Soner Sezer

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