Thunderbird Sent Emails not appearing in Sent Folder
I'm using Thunderbird as my email client and have it connected to my company's Microsoft 365 email account.
When I send an email from my phone or through Outlook on the web, the message correctly appears in my Sent Items folder.
However, when I send an email from Thunderbird, the message is sent successfully and the recipient receives it, but the sent message does not appear in Thunderbird's Sent Items folder or in Outlook on the web.
I've also confirmed that Thunderbird is configured to save a copy of sent messages to the Exchange/Microsoft 365 "Sent Items" folder and looked through numerous sent folder forum posts that don't exactly mirror this issue.
Does anyone know what could be causing Thunderbird to send the message successfully but not save a copy to the Exchange Sent Items folder?