Thank you, Jhieminga - the email address is ********** @hotmail.com. So far, all attempts to refresh/ reactivate it have offered a 'Forgotten password ?' option. Trying that produces the instruction to acknowledge a multi digit code which has been sent to the problem address ... which is not accessible ! hence Catch 22
PS ...Just realised that the provider is hotmail
NOT mozilla, and there are hotmail support sites ! Will have a rummage there .
Apologies for yet another 'Senior moment'