DNS CNAME for www alias not working

Question

I have registered a domain name at one company (Company 1). Because of hosting problems, I moved the hosting to another company(Company 2), and registered 'Company 2' name servers as the NS record at Çompany 1'.

So far so good, everything works. Except for 1 thing, the www alias is not working anymore. In my DNS settings at 'Company 1' I registered www.mydomain.com as a CNAME for mydomain.com, but this doesn't seem to work.

Does anyone know how I have to register www.mydomain.com ?

Answer 1

Does 'Company 2' have the SOA of your domain or is it 'Company 1'? If you're not sure, use the DIG command to find out. (Too low rep to comment)