To find out who is managing your domain names, you can do a WHOIS search.
To do this, do a Google search for the term 'WHOIS search'. You'll find numerous websites that allow you to search the WHOIS records for your domain names. The WHOIS records will include details about the company who manages your domain names.
Does my domain name management company need to add both values for the A record?
If possible, we suggest that your domain name management company adds both values (126.96.36.199 and 188.8.131.52) as your domain name's A record. If they can only add one value, they can use either one.