A while back I ordered a “clip-on” USB-C dock that had a power passthrough and had to send it back because the dock function worked but not the charging.
Sometime later I noticed that my USB-C->A adaptor wasn’t seating correctly because its plug wouldn’t go in all the way into the Hi10’s USB-C port. I filed away some material around the adapter plug base, effectively making the plug maybe 0.5mm longer. Since then it seats much more securely and no longer comes loose easily.
On a hunch I ordered another USB-C dock with PD charge support (a Wavlink with just 4 USB3-A ports and a maybe 15cm long connection cable). It too failed to charge, until I made its plug longer too. Lo and behold, now it charges (so it’s been glued to the tablet’s back 
)