Dead Tasmota flashed Bulbs

Please help my erudite friends!
A year ago approximately i set up many generic RGB bulbs and flashed them with Tasmota.
They were all working well, but were then removed and not used for well over 6 months.
Recently when i have tried to power them up they are all completely lifeless.
I am hoping someone here can help me to resurrect them.
i have tried the multiple powering on/off combinations, all to no avail.
Can they be re-flashed, have they lost their identities?

So you can’t reach it from GUI ?

You may need to do this ?

Does their AP show up in the WIFI environment?