Netgear GS108E cannot access web GUI through VLAN

Good afternoon,

I have the following scenario: my new home network includes a XS708T (192.168.15.1) switch, another GS108E (192.168.15.5) and one last GS105E (192.168.15.50). I have configured VLAN 500 for management (192.168.15.0/24), and so far it works well, except for the GS108E.

Take a look to the following configuration:

XS708T/port4 (Tagged 100/200/500/1010, Untagged 1, PVID 1) -> GS108E/port1 (Tagged 100/200/500/1010, Untagged 2, PVID 2)

GS108E/port2 (Tagged 100/200/500/1010, Untagged 2, PVID 2) -> GS105E/port1 (Tagged 100/200/500/1010, Untagged 1, PVID 1)

Port8 for XS708T and GS108E, and port5 for GS105E are configured as management ports, with only VLAN 500 as untagged and PVID.

What I want and expect to do is that if I connect to any device's management port (there are others apart from these three), I will be able to access the other devices located in the management VLAN. And this holds true, except for the GS108E. When I connect my laptop to the mgmt. port of the XS708T or GS105E, I can access all management GUIs of the network except for the GS108E. When I connect to the mgmt. port of the former, I can access all of them, including itself. VLAN 500 is not routed by any means, so it's not a routing problem.

I'f reset the configuration, checked ports and cables, etc. a couple of times already, but I'm starting to wander... I could use any help. Thank you!