The servers are secure, but it's still possible to become infected due to software and script installations I can see that several of these sites have wordpress installed, and wordpress software is some of the most heavily compromised web building software used online.There may be files hidden in there that are giving them access to continue creating backdoors and making changes also, I can see that you have several wordpresses for your sites, and some of them are on very old version Wordpress updates are typically done to patch up security holes and areas that can be easily compromised/infected So it's possible that one of your sites was found to have a vulnerability and this was exploited It's important to keep all software installations on websevers up to date to prevent this.
If still you are Facing any issue Please Click Here to raise a ticket to our Support team.
