WD my passport wireless pro - Network Password?

Hello all and thanks in advance for any help or advice.

Have owned a WD wireless Passport pro for a couple of years without any real issues.
A couple of days ago it suddenly, and without warning, would not let me sign in. I know I am using the correct password (the same one as I’ve always used) but whatever I do it reports that the network password is not correct. Have tried also from my iPad and its the same. I no longer have the box or plastic sticker that (if i remember correctly) had the factory password in that it had when new. So i am really stuck and desperate for help. I didn’t realise that WD don’t have any support themselves (which is dreadful in itself) and the only way of resolving things like this is here in the WD community knowledge base.
I am toying with the idea of reformatting but that isn’t really going to help if I don’t even have the default network password.

Any comments, advice, guidance or solution would be gratefully accepted.

Cheers, Brian