The blade assembly is either jammed or broken. I would remove the assy and test to see if it runs. If I you have isolated it to the blade assembly. (If not its internal and needs factory service).
Heres a link to the manual. The graphical instructions for removing the blades are on page 4.
First, I'm not a Andis Tech.
* Check your warranty and call for service.
*** Following is for information only ***
* Normally I would suggest cleaning and tightening the 2 blade holder screws as in a normal "Human" hair clipper. But I noticed this pet clipper uses a snap on blade (or a combo blade as shone in "Blade Maint" video. Looks like it's mostly cleaning though I have seen other vids with clippers going dull during pet "rescues" having to trim matted hair. One lady used 2 blades and ending up using a 3d blade. It could be just that; really thick dirty hair. Dirt and grime is a collection of stone dust and oils after all.
* Demo; https://www.youtube.com/watch?v=Aun5QDCtGgc
* Blade Maint; https://www.youtube.com/watch?v=v-rS_YQ-ro0
* Basic Repair; https://www.youtube.com/watch?v=CRGEQHhfCIc
* Repair (detailed); https://www.youtube.com/watch?v=pbDLhMugSgg
Aloha, ukeboy57
install the clipper blades onto the unit properly
read the user manual on how to do it
From your description it indicates that the blade base is on the tang but the clipper is not inline with the activator and will click in a bit more
get a small shallow dish and put in a small amount of kerosene
turn the clippers on and place the cutter blades( just the cutter blades ) in the kerosene so that any gunk , hair etc is washed out
change the cutter head to a newly sharpened set
There is a part called a blade drive assembly often referred to as a Lever there should be a spare in the case when you bought them. Try changing this part first but it's hard to find a good sharpening company in the uk. If you have any problem please contact
Send the clipper and the blade back to whoever did the sharpening for you and let them figure it out for you. It's not unknown for a sharpen to be "bad"