INTERNATIONAL ROAMING SERVICES

Hello,

I have my GSM phone number from TIM in Brazil with INTERNATIONAL ROAMING activated,... it has an IMEI number I can retrieve and test with *#06#

It worked for a period and I was able to send texts make calls for a while then,... problems on registering = LIMITED SERVICE ONLY (emergencies)

However it does not REGISTER with any network when using TRI-BAND OR 900/1800 bands

VODAFONE UK - message = Area not allowed
o2 - /uk - message = network error
T-Mobile - message = network error
Orange - message = network error

How can I test the number ???
SIM placed in any other 'open' phone has the same errors.

The number has credit. (pre-paid) Why is there only a LIMITED service???