Queues hanging

queue hangs and i get the message saying number is not in service when I try to transfer the call internally to any language queue ,but after I run dialpan reload on asterisk cli ,everything works fine .the problem is that it happens intermittently.

No such concept as “language queue” in Asterisk. If this were a problem using Asterisk, you would have wanted the Asterisk Support forum, but as it is not, you need to find out who supports the dialplan you are using.

If this is a relatively simple dialplan (in particular not one from FreePBX), please provide the dialplan, a trace at core set verbose 5, and an explanation of what it is trying to do.

ok no problem , i will send the trace when it happen again