Arduino BT can not upload

Hi everyone
I set the MUX mode of Arduino BT and it can not upload anymore, so I use avrisp to disable the MUX mode and upload some other code to test, I found wt11 now can connect to my computer and I can also send message like"AT" or “PAIR” command to my computer but WT11 never response(i.e. I send AT it should response OK) and arduino BT still can not upload(I use avrisp to upload)
I thought it is command mode and data mode problem, but I have try to change the mode, wt11 still can not send message to host(arduino), does anyone have some suggestions?
Thinks :drooling_face: :* :astonished: :astonished:

:slight_smile: :grin: :disappointed_relieved: :fearful:
some suggestions???