I am having trouble getting this plug in to work properly.

I am having trouble getting this plug in to work properly. The site has recently been compromised. I have removed all of the rogue files I could find and updated everything and intended to use Defender to scan for any leftover files. I've completed the hardening list ok but it refuses to run the scan saying "Your server resource usage is too close to your limit. Please try again in 15 minutes." I can see at least 5 issues that need fixing but when I click on "FIX ISSUE" it just gives the same message. I have granted support access