Website crashes after adding images

Hello,

I’m working on this webiste and a problem occurred after I tried to upload my own photos to the site. I firstly tried to upload my photos to the media library and aproximately half of the photos didn’t upload due to HTTP Error. I deactivated all the plugins and then tried to upload the photos again and I was successful. I added them to the header slider, reactivated all the plugins and the website worked as it was supposed to.

After that I tried to upload the same photos to the photo gallery plugin but the photos were uploading for aprox and hour and it couldn’t be stoped so I had to delete the plugin. I installed a new one and tried to upload the photos. But the same photos as in the media library failed to upload. Therefore I deactivated all the plugins except the photo gallery plugin. I tried to upload the photos again and I was successful. Then I activated all the plugins back and placed the gallery on the website. Unfortunately, the website crashed and didn’t show anything. I thought that it was a problem with the plugin so I deleted the previous one and installed Envira Gallery. I once again tried to upload the photos but the same photos as before didn’t upload. I repeated the same process as before – I deactivated all the plugins, uploaded the photos, activated all the plugins back and put the gallery on the website. When I tried to load the website it crashed again. I realized that it wasn’t a problem with the gallery plugin so I tried to troubleshoot the other plugins on the website. I deactivated all the plugins except the Envira gallery and reloaded the website and to my surprise it was working. After that I activated all the plugins back one after another and I always reloaded the website to see if it worked and , surprisingly, I activated all the plugins and the website was working properly. After that I tried to open the website on my mobile phone but the same problem as before occurred and the site didn’t load.

I really don’t know what to do to solve this problem and I would be very grateful for any help.

Best regards,
Filc