Not able to register SIP trunk

Asterisk Asterisk SIP
1

My sip provider has given me -

  1. Username
  2. Password
  3. Domain
  4. Proxy Address
  5. Authname

Suggest register string.

2

You have to check the responses for your REGISTER requests. In CLI

sip set debug on
set set debug PROVIDER-IP

If there are no responses, check your firewalls and the firewall of your SIP provider.
If there are, they should contain a reason why REGISTER fails.