1994 Plymouth Voyager iM confused About this

Well my 1994 plymouth grand voyager. When I turn it on it acts like if there is no gas, and I know it only has like 1 gallon or 2. But when I took it to the gas station to fill it all up when I was filling the tank, the gas pump made like a stop like if my gas tank was full and I know its not full, im confused like I think that maybe the tunell where the fuel goes through to get to the tank may be clogged up, or I don't know. It din't do it back then, it bearly started doing it like about a wee ago.