How to use three monitors on a laptop with linux mint through hdmi and usb-c

I have an HP EliteBook 840 G7 Notebook, with Linux Mint 20.3. My goal is to connect two more monitors to the machine. I have a monitor connected via HDMI port, and a monitor connected via USB-C port. Both monitors at the moment work if connected individually, but if I connect both, the one on HDMI takes over, and no signal goes to the one connected via USB-C. The strange part is that I have been able to work with three monitors for some time, up until (several months ago) I have upgraded the system (from 20.1 to 20.2, I think) ad I lost this ability. After reading this answer I have tried to change settings in the bios (allocated bigger video memory, and "enabled high resolution mode" (something involving USB devices in a dock, and Gigabit NIC), but I had no results.