adding new valves triggers relay to go offline

Trying to add new valves as one of the old ones went faulty - as soon as i add the valves the relay goes offline.

Is this related to the fact this is a 1st gen relay/thermostat and adding new valve would exceed the 5 limit ?

If so this is extremely poor software management that it would trigger to take the whole setup offline if you try to add one too many valves