I would have thought that you could set your account credentials, for example, as follows:
First Name> Your Forename
Last Name> Your Surname
Yahoo Username> Lynn_Mxxy (or something of your own! and yahoo auto adds @yahoo.co.uk)
Password> Use something like L0veMyPassword10 (best to choose one of you own! but make a note of this to remember the exact Upper/Lower Case lettering that you use. )
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