1999 fourtrax 300 4×4 Carb issue

My 99 fourtrax carb has been rebuilt and it was running fine. I put nothing in it but non ethyl gas with sea foam added in. It mostly sits until hunting season, but is started and left idling until the muffler is hot 2 or 3 times a month. It recently has gotten to where it will idle but won’t take gas when trying to accelerate. Any ideas on what may be wrong?