Huawei IP bts3900 migration

Hello:
We have a problem with one BTS3900 in our network, we did a IP migration:
Just connect the bts via a different subnet, modify ip, iprpoute..etc.
After the modifications the BTS never work.
Fallback to all parameters work perfectly.
Check IP parmameters, all Ok.
Check transmission parameters, all ok.
Delete, recreate the transmission path, still not working.
Change GTMU, still not working.
Change transmission router, still not working.
The BTS is still not working, we have opened a ticket to Huawei but any suggestion is welcome.