Parts in this thread regarding overwriting the ports tagging from devices’ configuration is very similar to my experience reported in thread linked below:
Also, if I set Devices VLAN to blank (remove 90) the connection to the Router is lost. It seems like blank is interpreted as Default VLAN 1 (?), as the corresponding Route10 Native VLAN is reverted to Default at the same time.
E.g. if I set Native VLAN 90 and Allowed VLANs 90 for a specific port, it gets set to Native VLAN Default by saving the Device with a changed static IP (or changing from dynamic to static IP) even though the Device VLAN was blank before. Reverting from a static IP to dynamic IP (delete setting and leave field blank) does not overwrite the Native VLAN for the port.