Untagged - the default tag it will be when a device with no VLAN is connected
Tagged - allow tagged traffic for devices configured with that tag
Trunk port - allow all VLAN tags

When a device without VLAN tags support is plugged in, it’ll be placed in the default VLAN

Switch configuration (Hasivo)

Proxmox
Change it to VLAN-aware (like a trunk port)

Hasivo & SiriVision