Hello,
Thank you for contacting us and sorry for any inconvenience that might have been caused due to that.
It seems like you purchased the plugin with some other email address. Can you please share the email address which you used to purchase the PRO plugin or you can search and forward the receipt from FastSpring.com so we can locate your account?
Back to your issue, one possible reason for this error is trying to update the PRO version of the plugin while connected to your free account.
For more details, you can check this URL:
https://rankmath.com/kb/fix-pclzip-err-bad-format/
Looking forward to helping you.
Thank you.
