Alias not working...maybe?

One of my accounts is setup to run on an alias. I think for the most part it is working correctly. However, I just sent an email and the “out of office” reply bounced back that with the gmail email address that the alias covers over. Any thoughts on whats up here?

ps…not super techy, so i apoligize if this is vauge and/or I might not be well versed to answer questions well in replies

When you generate a new email, eM Client defaults to the original address of the account as the sender. If you want to use an alias address as the sender, click on the down arrow to the right of the default sender at the top of the email you are creating. This will give a dropdown list of all possible senders including created aliases.
Unfortunately, I believe that there is no way in the program to make any other potential sender the default. You must, therefore, choose the alias each time you send an email. Otherwise, it will go out as the default. Perhaps someone else knows of a way to change the default.

eM Client will use the email address of the account folder you are in when you start a new message. You cannot choose an alias address as the default.

When replying to a message, eM Client will reply using the alias address if the message was sent to that address.