Evo 3g signal problems

Hi guys!

I have been facing a problem since 3 November.The signals on my display for EVDO are not present instead just a x while when on 1x mode full strength signals.Now i have been using this device (black dongle ,glossy finish ,bought it in august 2010) last year.I have a ptcl tower just few hundred meters away from my house. The area where is not very populated and i had the full signal strength and speed (app. 300__360) and I was satisfied with the service (except for a setback which took place last year in october/november) but now I don't know what to do.I have used device in different directions but to no effect so what should I do?

EVDO carrier in your area has stopped working, might be.