Make sure the following is done:
In the frame, the channels going to an LQ should be configured as LQ-SIP
The LQ sip accounts are registered to the sip server
The LQ sip accounts and LQ-sip channels going to the frame are assigned as “Directs”. This creates a one-to-one relationship
To call out from a panel:
Dial 1 plus the number.
Select the sip interface.