Two lines on SIM-cards

Greetings.
Faced with such a problem.
We have a Asterisk (FreePBX) and GSM-gateway Dinstar DWG2000F.
Configure incoming line from SIM to queue.
Issues:

  1. When an incoming call on the second line of the first cut off the conversation.
  2. Sometimes the call generally “stuck” in the PBX does not reach by telephone.

Who faced? Generally queue to Asterisk working with the second line on the SIM card?

Thank you!