Hi I'm having a similar problem, since I upgraded clean up to pro, Antivirus has reverted to free version with ads and every time I try get activate pro I keep getting the same message "error retrieving data, check Internet connection and retry".
Obviously no Internet connection issues so not sure why I'm receiving this message, found this forum the ad and tried the steps above of uninstalling, clearing play app data and play services cache, resetting and reinstalling, for both antivirus and clean up, unfortunately to no avail. Since I can't activate pro, I no longer have linked access to direct support.
Please help, if anyone knows how to resolve this issue I would greatly appreciate some advice.