I have the leather wireless charger from Samsung that I use to charge my Galaxy buds all the time, but when I go to use my phone on it, without fail it'll start charging but 5 seconds later it says "wireless charging paused." It's a little infuriating.
I recommend you bring the phone to SAMSUNG Store and get diagnostic. maybe there's defect on your phone. Note 10 plus release date is August 23 so your phone is still under warranty. I hope you get service from SAMSUNG.