wordpress wont show uploaded pictures

Hi, i have a few plugins that user can upload images. If they upload images above certain dimensions, say 2000x2000 the plugins resize them

But after uploading those size images i get a blank screen with just the background on it.

smaller size images work fine.

The settings are correct to allow for the large sizes. Iv checked the server settings to allow large sizes and time execution. Then I found out that they ARE being uploaded to the wp-content/uploads folder so its not the server.

Its also no the plugins because its happening with ALL of them.

it must be a wordpress problem.
In the uploads folder where they are the file permissions are 644, i dont know if this makes a difference. ??