Are you a TalkTalk Consumer broadband customer?
Provided the password has not been reset then if you're a TalkTalk broadband or MailPlus customer and know the current password you can change your email password in MyAccount > My Services > Manage TalkTalk Mail.
Here's the advice article on managing your email in MyAccount.
But if you're saying you forgot the password and haven't set up Reset details for password recovery then the TalkTalk team will need to verify you as the registered mail user and set up new Reset details for you.
Password Reset details should have been set up for the email address so that an alternate email and or mobile number can receive a password reset. Please do try the Forgotten your Password option. If there's an alternate shown that you recognise from the hints, and have access to, then please reset the password.
Let us know and we'll take it from there.
In the meantime, please update your Community Profile Personal Information (Click here) to include your name, current contact 'phone numbers and address with postcode (location) then scroll down to Private notes and add the email address and Save changes.
Did the advice from @Gondola resolve your issue or do you you still need help?
If so can you please update your community profile to include your:
We'll then look into this further. Please do not post this information on this thread. Once you've updated your profile please post in your topic to confirm it's updated.