I have a MICS 6.1 with a 6 port fiber expansion, two 0X16 and two 12 X 0. I have 4 pool groups A,B, C and D and have assigned 9 for pool A and 8 for Pool B...I am trying to assign a different access code for pool groups C and D but cannot. i have 3 digit extensions starting with 221. Any suggestions ?