You cannot add a CNAME record due to an incompatibility issue.

Oldies but goldies
1

Hello
Can't add CNAME record:

This sub-domain is already using a DNS record. You cannot add a CNAME record due to an incompatibility issue. Please delete the existing records for this sub-domain to add a CNAME record.

2

Did you receive an answer? did you find the solution?

3

I have the same issue. Feels like a bug, I don't even have a single CNAME record on that domain…

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