Here I will tell you a website
Saipan Mobile Phone Forum. Go there to find the model number of your mobile phone. They will make certificates every day
As long as You enter the IMEI number of your mobile phone, which is the number combination that comes out when pressing *#06#. If you encounter similar problems in the future, just use the mobile phone certificate signing software and then install it.
It is recommended that you submit your information from 10:00 to 12:00 every day. He will collect the information during this time. If it is quick, it can be downloaded on the same day.
I have tried it on a Nokia 5320 machine.
If you think you can give it a good review.
Some FAQs and software can be found here.
Another note:
I am not advertising, just recommending.
I thought it would be useful so I shared it...