Half my frontend images not loading

Hi,

I’m a bit of noob to this, so please bear with me.
I was a free WordPress user for many years, and finally took the plunge and purchased a premium WordPress account so I could finally use some of the cooler features from WordPress.org.
I downloaded a plugin for Instagram and shortly after noticed half my images weren’t loading on the frontend anymore. They’re still visible as thumbnails and editable images on the backend in the media gallery, but the url to a broken image won’t load it up. I read through this forum that maybe it might be the Instagram plugin, so I disabled that.
I installed the Health Check plugin and ran it, and funnily enough the images at least loaded this time, even if on the homepage they didn’t crop like they’re supposed to. But since I understand so little about this, I have no idea how to check if something else might be wrong or how you would see it.
I also made sure the lazy loading images part of the Jetpack plugin was disabled, as I read that caused some people problems.
Otherwise nothing has changed on my blog in quite a while. The images are uploading as /wp-content/ and my blog is on https, so I’m running out of ideas and knowledge as to what might be causing this problem.
I was able to discern that the actual URL for the images are still fine, but for example when looking at the attachment page of an image, it won’t load up.
Any help would be greatly appreciated as this is now quite a bit out of my depth of knowledge.

Thanks,
Franzi

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