I’ve seen the same with a 5w and 12w apple charger and one of the powered USB ports in my Lenovo port extender “dock” will not charge even with an apple cable - never had that issue with my 6s on that port.
I too am having this issue with my XS Max. Seems to be fussy getting the charger to register.For some reason, my iphone Xs max is not registering the charger. I have to usually pull to try plugging it in twice. Is anyone else having this issue?