Hi @Babbles,
I did some research and found some resources on the Plesk and Let’s Encrypt websites, please take a look if these help:
- https://support.plesk.com/hc/en-us/articles/115004728413-Unable-to-issue-a-Let-s-Encrypt-certificate-The-token-file-is-either-unreadable-or-does-not-have-the-read-permission
- https://support.plesk.com/hc/en-us/categories/201413825-Technical-Questions
- https://community.letsencrypt.org/t/invalid-response-on-acme-challenge-but-can-access-files-in-the-directory/69108
- https://community.letsencrypt.org/