I can't find its specs but it should use one of the following AC Adapters (chargers)
200 W part # L00818-850
150 W part # L32661-001
135 W part # L15534-001
Your dock only gives 85W that why it won't charge your machine (actually it can charge your machine overnight or when machine is nearly idle).
I tested my HP USB-C Gen 5 dock (out 100W) with 4 of my machines (because they have USB-C or Thunderbolt™ 3 port.)
(a) HP Elitebook 840 G5 with Thunderbolt™ 3 port - PSU 65W (b) HP Omen 15-dc0071tx with Thunderbolt™ 3 port - PSU 200W (c) Dell Inspiron 2-in-1 13-7000 series with Thunderbolt™ 3 port - PSU 65W (d) HP Envy x360 15-ee0047nr with USB-C 10Gbps with PD and DP 1.4 - PSU 65W
The dock gives 3 FHD external monitors for all but it won't change my HP Omen. I'm using it on machine (a) now and they are TRUE mates with a single cable solution (power the dock will power machine and shutdown machine will power off the dock).
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