i need to change extension number for fax device ata 190

[Mahmoud0111]

Dears ,,

i would like to change fax extension to be 215 instead of 1143 

when some one outside calling us and enter Number 6 for fax it's transfer to extension 1143

i need it to be on 215 this number when outside calling us for fax enter 6  it's needed to be transferred to 215

thanks in advanced

[Mahmoud0111]

can i change the Directory numbers digits to 3 number instead of 4 mgogna  

can u advice me on this one

:)