I have a blueyonder email account and I am unable to access webmail anymore.
So what error message are you seeing when you try to access the account via the Virgin Media webmail from here https://mail2.virginmedia.com/ ?
If it is the "Your mailbox is unavailable.........." error you may be able to unlock the account by resetting the password.
However, if you do not have a VM broadband account, or if you do but this Blueyonder email account is not linked to it, VM may well be in the process of closing your email account.
According to their Terms and Conditions, 90 days after a broadband contract is closed VM should delete any email accounts linked to it. However, they sometimes take years to catch up with these "orphan" accounts and then they simply delete them without any warning. See D6 here Terms-and-conditions-for-fibre-optic-services#broadband
Hopefully you are not in that siltation but post back here with the error message you are getting from that link.
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