RDNS configuration error

I am having this error in the RDNS configuration of my dedicated server: The system failed to complete validation of "xxx.xxxxxxx.xxx"'s "PTR" because of an error: (XID h23c98) DNS returned "SERVFAIL" (code 2) in response to the system's query for "xxx.xx.xxx .xxx.in-addr.arpa"'s "PTR" records. I do everything to solve: 1- I have already contacted the data center where my server is and they helped me set my localhost to the main IP of the server, according to: Could you help me find out what I'm doing wrong?