Beccer-Tree wrote:
New. I am using Proton mail. I have been using them for a long time. About a month ago things started disappearing. Before that there was no issue. I updated the operating system to see if that would help. Id did not.
well Proton is known to be problematic. ref Contact Proton support
see raving reviews——
"Temporary? This is an on going issue. I have been having problems even sending email for ... Years. I even have the paid account because even after I cleared my mailbox it still said it was full. Your system is seriously ******. Every other day there is a problem. I just haven't had time to change EVERYTHING over to a different service. Proton mail is hands down the most problematic email service I have ever used.”
ref:https://www.reddit.com/r/ProtonMail/comments/bgs6vy/protonmail_down_incoming_emails_are_not_getting/
However for your issue— if local Mail.app—
problem accounts the go to way to sort an issue like yours—simply remove the account and add it back in and see if it resolves. If not Proton is your best way forward for support...
Remove email accounts in Mail on Mac
Remove email accounts in Mail on Mac - Apple Support
Add email accounts in Mail on Mac - Apple Support
Add email accounts in Mail on Mac - Apple Support
Note—
IMAP accounts stay on the server, so no local loss, when you re-sync
POP accounts download and remove from the server—therefor save your inbox/sent box if you want them
On My Mac" is just that, local folders you created and moved mail into. So no loss