Hi
I am also getting the same error message while trying to create a Zap between Plug&Pay and Mailerlite.
The funny thing is that this Zap worked smoothly last month and now there is this error message:
“Failed to create a subscriber in MailerLite
MailerLite API returned an error: The given data was invalid.”
I have tried every single suggestion in the above mail chain but nothing helped.
Anyone any idea how to get rid of this error message?
Thanks a lot.