About FreePBX and TE121

Hello,

This is my first posting so if I am doing something wrong, have a little of patience.
I installed Asterisknow 1.7.1 with Asterisk 1.6.2.17.2, DAHDI 2.4.0 and FreePBX 2.7.0 and the card of Digium TE121.
The configuration is good and did the signalling configuration in the page of FreePBX. It works, I can call and receive the calls.
But if I reboot the system, the page FreePBX complains that found a new hardware and need to configure again the the TE121 in the FreePBX, although the configuration in dahdi and asterisk did not change from before the rebooting.
And I am unable to call or receive the call until configure it again in FreePBX.
It happens in every reboot or shutdown of the system.
Has anyone come to this kind of problem?
I tried to look for this problem in the forum and internet but did not find anything.
Thank you in advance for the help.

All the best,
Wei