2001 Traxter, Is my clutch slipping?

Hi, Hoping someone can help.

I bought a 2001 Traxter 5 speed about 2 weeks ago and it seemed to drive fine. It has a set of tracks on it and I could put in in high and shift through the gears manually (when i switched to auto, the engine would rev but bike would not move.) I could go through the snow, up hills all seemed with no problem.

Well it started to lose power/drive but engine would still rev just tranny would slow and bike would stop.
Now it will only roll a foot or so in high gear and if I put it in low it will go better, did get it up to 3rd gear but would still lose speed and stop but the engine keeps revving.

is this a slipping clutch or could it be something else?

I did notice before this that it seemed that when throttling up the bike would move slowly and then all of a sudden it would catch and would take off.

I have downloaded a manual and have been reading through that.
I was thinking of trying to run the diagnostic/calibration and have read that the jumper is just a wire so i was looking for the connector and I think I found it but it has 3 wires in and 1 wire out, is that right? I thought it would have 2 wires.

Also noticed that the mileage does not show anymore as it did when I bought it. 1700km/mile not sure

Thanks for any help and feel free to ask for any info.
Also using BRP 4 stroke synthetic oil and just did a oil change and no diffence.