It is unfortunate you were assigned an unresponsive sponsor. It is not your job to revive your sponsor.
I would recommend the following steps to solve your problem
1. Try communicating with your co-sponsor, they are also available to help you. If that does not work go to step 2.
2. Go to https://www.sfimg.com/MyAccount/upline and select a person from your upline to help you.
If these steps don’t help submit a support ticket and request a new sponsor. State your problem and the steps you have taken.
It is possible your sponsor is not fluent in your language and is intimidated by this. It takes patients by both parties to use a translator when communicating. I would request a sponsor from my own country / language group if you decide to make the request.
It is not SFI intent to make getting help difficult. I am currently helping an A2A friend who has two unresponsive sponsors. There is someone who will be happy to help you.