I have two Dell S2721DS connected and the dock works perfectly

HP officially only supports HP ProBooks and HP EliteBooks with Thunderbolt connection. Theoretically, however, notebooks from other manufacturers with a Thunderbolt port should also fit. Your notebook appears to have such a connection. The dock may or may not work with your notebook. I recommend that you opt for a dock from Dell. If the worst comes to the worst, you will get support for the entire combination. Btw: The Dell S2721DS from @ortlud are screens. These are logically compatible with the dock.

I don't know