I'm working on a website that has over 300 images, using WordPress 5.1.1 with Classic Editor enabled. In Media Library, I can view all the images since it uses pagination. However, when I click Add Media from a page or post, it lazy loads ~40 images at a time, but is getting stuck at 101, so I can't select any images after that point. When I monitor the network, it requests admin-ajax.php over and over again, with the response being the 101st image.
How can I go about fixing this? I tried activating the default theme and disabling plugins, no luck. I also increased max_execution_time and memory_limit in cPanel. Tyia.