How do I stop 'Malware Blocked' pop-up (PT.updd) from repeatedly appearing on Mac?

UPDATE: i went to the activity monitor, alphabetised all files and found ander PT.updd file. managed to delete it. Seems to have done the trick! I was here: /Library/PrivilegedHelperTools/PT.updd

Hi!

Since this morning the same pop up (see photo) keeps popping up. Malware blocked. PT.updd was not opened because it contains malware. Very annoying. After reading up in the community I looked at

~/Library/LaunchAgents

/Library/LaunchDaemons

/Library/LaunchAgents

And deleted a PT.updd file, as well as some other weird files. I thought that would do it. But no. I also emptied the trash and restarted my computer. I don’t have popcorn time installed.

Now I am at a loss for what to do next.

I will be so grateful for some help, I have to give an important presentation later today and this is making me quite nervous and distracted.

Thanks!

Barbara

[Re-Titled by Moderator]