Certificate error on 1 of 2 email address but not the 2nd

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Issue abstract: I have 2 email addresses on the same domain. a@xx.com and b@xx.com. Norton stops outgoing emails from a but not from b because of expired certificate(s)

Detailed description: I am using outlook 365. As far as I can see all settings on both email accounts are identical. the outgoing is smtp.xx.com and the ports are identical. same with encryption settings. But norton will let emails from b@xx.com go out but stops the ones from a@xx.com

Product & version number: norton 360 24.11.9615 (build 24.11.9615.893)

OS details: windows 11

What is the error message you are seeing? We’ve identified a site certificate problem

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