HP Spectre X360 16" will not charge with 90W AC Adapter

[SubGrid]

The HP Spectre X360 16" I have came with a 135W AC Adapter. This adapter stays at a desk and would like to purchase a 2nd AC Adapter for travel, however these are next to impossible to find for purchase separately thru HP. I have a few different 90W AC Adapters that I have been able to use as a 2nd AC Adapter for travel for other older Spectre X360 models without issue. When plugging a 90W AC Adapter into this brand new Spectre X360 16" model, the orange light turns on and the computer recognizes it, but will not charge the battery. When running the battery check thru HP Support Assistant, it shows 0mA of current on the battery. The battery does not drop any percentage at all. It just maintains the current percentage. If I unplug the AC Adapter, the current will show anywhere from 1000mA to 2000mA depending what the computer is doing. When plugging in the 135W AC Adapter, the current shows 6900mA (which is the rated current output of the charger).  The 90W AC Adapter is rated for 4600mA, so should have plenty of capacity to charge the battery while the computer is on. The 90W charger will charge the battery just fine if the computer is powered off. It seems like there is some type of software setting somewhere that is disabling charging when it sees the 90W AC Adapter.  This is also not just an issue with one computer. I have a small business with a number of these newer 16" Spectre X360 laptops with the same issue. 

Has anyone else experienced this and have a solution other than to try to find a genuine 135W AC Adapter to buy? I keep checking the HP Parts Store and HP.com for a 135W AC Adapter, but have not seen one available on there for quite some time. I understand that at 90W, the charge time would be longer but would gladly take a slow charge time as opposed to not charging at all.

[banhien]

@SubGrid 

90W is too weak. You need 135W or above. Your 90W charger should slowly charge your machine when NOT in use (off, or idle or sleep)

Regards.

[SubGrid]

The numbers don't support that though. If battery is drawing 2000mA (or much less if brightness is turned down) and 90W charger can output 4600mA, then there should be 2600mA available to charge the battery. Instead it is just a flat 0mA. Something is disabling charging. Battery actually charges fairly quickly when computer is off.

[SubGrid]

I also just tried a 65W, 90W and a 110W USB-C charger and ALL of those charged the battery just fine. Its only the normal 4.5mm AC jack that will not charge with anything less than 135W.