Could anyone help fix my heater?

Squeeze the heater hoses going to the heater core while then engine is running. Are they getting hot and feel pressurized? That will tell you if hot coolant is flowing to the heater core. If yes, then problem may not be with heater core but the blend door. If no then you have to figure out what is interrupting coolant flow. Regarding the blend door, it may be stuck in the 'cold' position, the actuator is often the weak link.

Check to make sure someone hasn't bypassed the heater cooling hoses. You should have 2 hises going from the engine to the firewall. Make sure they're not connected together. One should be connected from water pump going in and the otherone should be the return going back to engine. Be carefull with hot coolant

The door is working correctly and I e owned the truck 7 years it always had very warm heat so heater core is not bypassed, it's got me puzzled I also put new clutch fan on and also new radiator about 2 years ago

Try bleeding air out again, park with the truck facing uphill, the steeper the angle the better, then bleed air out. You want the radiator to be the high point when bleeding the cooling system.

Until u check coolant flow, u'll be able to pinpoint the problem.Process of elimination.