Problems with Thunderbird (on PC) and Gmail on android


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Hello. I am having problems with Thunderbird (on PC) and Gmail on android. Same domain. I have not received emails on either in two days. When I try to send emails from my android (google) the sent emails go directly to outbox and stay there.

When I try to send from Thunderbird, I get this message, "Your message was sent but a copy was not placed in your sent folder (Sent) due to network or file access errors.
You can retry or save the message locally to Local Folders/"

Then I go to my website (I am self employed) and get this message, "

Your connection is not private​

Attackers might be trying to steal your information from (for example, passwords, messages, or credit cards). Learn more


Next to web address (very top left) reads, "not secure". When I click on "not secure" I get a message that tells me that the site is NOT secure and that then certificate is NOT valid. That it is only valid 2/4/2022 05/6/2022.

what should I do?