I had the CV boot replaced but the clamp keeps coming off. What should I do?

It sounds like the wrong boot was put on. There should be a small lip on the joint housing that keeps the clamp in place when the clamp is properly tightened.

Do you think that I have to replace the whole axle? When I called the auto store I bought it from they told me that it was the correct part and that I may have to replace the axle because that's what is making the sound?? They also said that it is hard to tighten the clamp because the part is packed with grease? Not sure that they are telling me the correct information.

Should I even be driving it since it keeps falling off?

They are full of the proverbial bovine excrement product. If the right clamp is sold with the right boot, it will stay on as long as you need it to. Most aftermarket boots come with a wormgear type clamp, where a screw is turned to tighten and loosen the clamp. Pull the boot back, wipe of the joint housing and locate the small groove the clamp rides in and slide the boot over the lip. Then place the clamp in the groove and tighten it until you are unable to move it by twisting firmly. Then bend the loose end of the clamp over the wormgear housing.

Parts store like to sell full axle shafts instead of boots because they make more money on complete shafts.

Don't drive it too much until you get the boot and clamp properly installed.

I will try that, thank you so much for your help!!

Let us know how it comes out.