Samsung s8 only charging to a certain % on wireless charger

I have a customer with an s8 the device is using a Belkin wireless charger which has been replaced twice now. It is only charging to a certain percentage with the wireless charger however it chargers fully with the USBC charger and with a portable battery pack.

I have replaced the wireless charging module and battery. The device has no case on it also. I have cleared the cache and a number of other settings.

Any other solutions?