do not pass a second call if first line busy

Hi
i have problem ...
there are some trunks to call on city numbers
to call on mobile numbers it's need: call on city number of provider,(pause) enter pin code, # , dial needed mobile number, #
i try custom trunk custom string ne don't understand pause,i think

then i have made so...
add to extensions_custom.conf
to internal-custom

exten => _89XXXXXXXXX,1,Dial(SIP/TRANK5/NUMBER_PROVIDER,,AD(WPIN#$[EXTEN]#)) ; w-pause
exten => _89XXXXXXXXX,2,Dial(SIP/TRANK6/NUMBER_PROVIDER,,AD(WPIN#$[EXTEN]#))

if i understand correct 1 and 2 ("2" try to change on "n" ) should set an operations procedure

the first call on mobile number its ok
if i try tocall on second mobile simultaneously, erorr the line is busy
Please note, although no boardcode and smiley buttons are shown, they are still useable