Nope, solved the issue, what has happened looks like a 2 fold issue
User mis management
I have a feeling I uninstalled by accident an automation connected to the affected device, not totaly sure but it appears that was what stopped the device responding as I use a virtual switch for on off
Incorrect Tuya integration
Tuya devices I now remember show as cloud offline by default when connected to ST, this gives the impression visualy of a faulty cloud connection … but.
If a virtual switch is used to connect the v switch ‘on’ to the tuya device ‘on’ and the v switch 'off 'to the tuya device ‘off’, the v switch operates the device perfectly fine, even though the Tuya integration shows offline
Currently using the new ‘automations’ tab to check old connections that are broken and fix them, which on a side note would have been a pig of job before the introduction of the tab