Too many certificates (5) already issued for this exact set of domains in the last 168 hours

Hello,
we use letsencrypt since 2018 for our mail server but this time,
we can't renew our certificat and get this message :
An unexpected error occurred:
There were too many requests of a given type :: Error creating new order :: too many certificates (5) already issued for this exact set of domains in the last 168 hours:.....

how to resolve this problem?

thanks

2 Likes