Suddenlink email account doesn't work on my iPhone 16

just got a new Apple 16. A suddenlink email account I use besides iCloud and Gmail is listed in Mail Accounts and function. However the suddenlink account displays only 64 prior emails and does not accept ones I send it now.

is there some other place I need to activate it on this new phone? The suddenlink account for my wife works on her iPhone and on my Mac suddenlink works for my account. Just not on the new iphone

thanks for your consideration

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