the hose from the air gap to the disposal is obviously the problem. This hose should be 3/4 or 7/8″ smooth ID hose. IE don’t use any of those corrogated drain hoses for this section. The hose should slope down from the air gap to the disposal connection, No looping down and then back up. The air gap should be as close to the disposal as practical, usualy on the kitchen sink or adjacent to it.
Check the opening into the disposal, make sure the knockout that closes off this hole when purchased was completely removed.
And lastly…and i hesitate to mention this because it implies that you are an idiot….but what the heck, this is the internet, if you don’t have a thick skin, you don’t belong here. Did you hook up the air gap correctly? smaller connection usualy angeled to the side goes to the dishwasher, larger center connection goes to the disposal.