Let's Encrypt new auth status 400

[nik00726]

I am getting error "Let's Encrypt new auth status 400" since a few days. I have a renewal coming in the next few days.
I have try solution here viewtopic.php?t=18618 but still, same error occurred. Some time I get error : Let's Encrypt new auth status 400 and sometimes: Let's Encrypt validation status 400