Inability to make/receive texts and calls and use the internet despite roaming internationally.

I have tried to get help through the chat for a week now but my issue has not been resolved. I have subscribed to roam International but am unable to make/receive calls or use my mobile data to connect to the Internet. I have now been locked out of my bank account and have already spent more than £50 while on hold to the bank unsuccessfully. I am also running out of money. I badly need to speak with my bank to uock my account. Could someone from ID help me use my phone please? I'm using the same handset I have had for the last few years so am not sure why I cannot roam. Thank you