I’ve had the same problem for a few years with my same machine. I thought it had the paper seal out of bottle cap for fuel additive which I saw fall in, floating around and blocking the tank outlet. I got stranded last winter blowing snow, very pissed off decided to pull the tank to flush it out. Very difficult and didn’t get the tank pulled. I did however find a pinched vent line for tank on left side to right, pinched by the ROPS. Replaced that line, haven’t had a problem since then. I can’t understand that line causing my issue the same issue your having, but a simple check to remove 8 bolts to see if the line is pinched there. Mine was the left mount on corner. Good luck
