If you’ve bought a new phone and you’re finding that it’s getting overly hot when charging, you should avoid using the wireless charger for the first day or two.
When you first set the phone up it can be busy for the first couple of days indexing and downloading/updating apps.
Combine this with the heat generated by wireless charging and it could cause the phone to get uncomfortably hot.
So give the phone a chance and plug it in to charge until things settle down.