[Lee]

The first problem I found with my 2013 Cougar is that the battery disconnect switch does not truly disconnect everything from the battery. Investigate what is still powered.

You have a single battery?

It should last longer than your experiancing. You may have a defective battery from the manufacture.

Charge battery up to 100% then disconnect the battery cables from the battery. After a week check and see if it's down to 1/3 charge. If so, battery is defective. If it's still at 100% then something is bring it down.