CHANUNAVAIL for specified line in Dial command

Hello. I have the record in dial plan for Asterisk 1.8.13.1

exten => _8XXXXXXXXXX,n,Dial(SIP/gsm2/${EXTEN}:4006,,M(setAnswerDate))

it calls to mobile throught gsm2 gate (AddPac Model : GS1004_G2) and sim card with 4006 hotline value. Here is all ok.
I install new asterisk: Asterisk 14.6.1 in another server. New dial string is:

exten => _8XXXXXXXXXX,1,Answer
same => n,Dial(SIP/gsm2/${EXTEN}:4006,,U(subCallWriteAnswer,start,1,${EXTEN}))

but in this case I always take error ‘CHANUNAVAIL’:

-- Executing [8MyNumber@internal:7] Dial("SIP/199-00000fd0", "SIP/gsm2/8MyNumber:4006,,U(subCallWriteAnswer,start,1,8MyNumber)") in new stack
  == Using SIP RTP CoS mark 5
    -- Called SIP/gsm2/8MyNumber:4006
  == Everyone is busy/congested at this time (1:0/0/1)
    -- Auto fallthrough, channel 'SIP/199-00000fd0' status is 'CHANUNAVAIL'
    -- Executing [h@internal:1] NoOp("SIP/199-00000fd0", "INTERNAL HANGUP") in new stack

If I remove 4006 it calls ok, but throught first free sim card, but I need specific 4006 card. Of course the sim card is free when I test that. What can I do ? Help.