Default [HELP] 3G not work, HELP ME!

Hello, currently I have the A953 Milestone 2.
I had installed the original firmware 2.3.4 Uk (Gingerbread) and my 3G working properly.
Install the 2.3.6 firmware Brazil Retail (Gingerbread) and could not create new APNs, then returned to the Uk 2.3.4.
Since I came back does not work the 3G signal.
My operator uses frequencies 850/2100 Europe.
Need to help me solve my problem, worked fine before, I always appeared the H (HSDPA or HSUPA), now appears only E (EDGE).
If I set to work only on 3G, stays in emergency call.

Sorry my bad english.
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Hola, actualmente tengo el Milestone 2 A953.
Tenía instalado el firmware original 2.3.4 Uk (Gingerbread) y mi 3G funcionaba correctamente.
Instale el firmware 2.3.6 Brazil Retail (Gingerbread) y no podía crear nuevas APNs, entonces volví a la 2.3.4 Uk.
Desde que volví no me funciona la señal 3G.
Mi operador utiliza las frecuencias 850/2100 Europa.
Necesitaría que me ayuden a resolver mi problema, antes funcionaba bien, siempre me aparecía el H (HSDPA o HSUPA), ahora solamente aparece la E (EDGE).
Si configuro para que solo trabaje en 3G, se queda en llamada de emergencia.