You could always try some clear silicone sealant. The stuff that comes in a tube like toothpaste. It dries like stretchy pliable rubber and is sticky as all get out before it dries. Make sure you've cleaned the hose end and the part on the vac where you are basically glueing it to.
Don't 2nd guess and think it's dry in 5 hrs.. ensure it dries for a day or overnight.