Idea Cellular — SIM not picking up the signals

Address:

Rwanda

I have been a customer of Idea for more than 10 years. I am currently on travel to Rwanda, Africa.
As I landed here, the SIM stopped picking up any signal.
International roaming is active on my mobile. The bills are paid. My credit limit is upwards of INR 23, 000/-
I have done what customer care told me. Restarted the device, selected manual network, and checked the SIM with another phone. No resolution.
I filed customer care and they gave me a TAT of 48 hours. Everytime I connect with the Customer Care over chat, the only answer I get is wait for TAT to get completed and we will surely resolve the complaint.
The customer service executives do not read the messages, do not understand the context and reply with standard texts.
This is a sheer harrasment.
SIM not catching signal has a lot of impact as I am not able to complete any banking transactions.