Post Type Switch Plug-in NOT SUPPORTED

Hi! Was hoping to convert a page into a post using the Post Type Switcher plug-in but upon checking, it says “NOT SUPPORTED” even though it says that it’s compatible with my version of WordPress. (here’s the link to screenshot for your reference: https://ibb.co/tzGtYRL )

I did try just installing it regardless to see if it works and it didn’t The option to switch it in the edit page/post page doesn’t show up even after I installed the plug-in. I also can’t “activate” the plug in, it automatically just says disabled and it’s not clickable.

I also checked my version of WordPress / PHP etc and they should be ok so not sure what’s wrong here. I’m a newbie at wordpress and just helping out updating stuff every now and then so I’d be grateful for your help. Thank you so much!