Homey bridge lost connection with Aqara switch T1 (no neutral)

And how many Watts is / are the connected lights? Higher than the minimum of 3 Watts?

In the same developers tool, go to Tools - ‘Devices’, and try to find the removed device here. When found, hit the bin icon on the right to remove it.

Yes, but your devices have to be paired again. Repair isn’t possible, while Homey sees them as new devices.
And the flows used with these devices have to be fixed.
But it can’t hurt to reset the Zigbee network.

When you have many flows to fix, there’s a neat script which can replace the device ID’s with the new ones
BUT you’d have to know the exact ‘old’ device names, and you’d name the ‘new’ devices slightly different.