So you don't actually have a visa, you have an "unable to travel due to covid" extension? So with air borders open, with multiple overseas airlines flying in and out, and just about every country around the world open, where exactly are you claiming you're unable to travel to? If you get a letter from your embassy saying your country is closed to incoming flights and present this to immigration, they may look at it with more empathy.
Google Volunteer Foundations Thailand and you should get some leads. Keep in mind however that you will be required to have a work permit and actually do the volunteering. The 50,000 baht bogus visas are in limbo as