Problem unlocking E/// 3G cell

[wave]

Dear experts,

I have the following problem with a E******* RBS6102 site:

If I lock a specific cell using bls command,
when I try to unlock the cell using deb command the cell gets unlocked but operationalState is Disabled.
I tried waiting for some time but the cell remained Disabled.

When I checked the alarm log I got the following message "nbapCause: message_not_compatible _with_ receiver _state"

What is the cause of this problem and how can I make sure it doesn't happen again in the future

Thanks

[wave]

anyone can help me with this?