Gpd win max 2 4g module unlock

Hello, it appears I am having trouble connecting to cellular data with my gpd win max 2. I did some digging online and entered my IMEI into a carrier locked checker thingy. Appearently it says its carrier locked to AT&T, and i only found that out after purchasing a sim card from US mobile. How exactly do I "unlock" the 4g module so that it accepts my us mobile sim?

If there isnt a way, can someone guide me with how to get one from AT&T?