Hi Karen, welcome and thank you for your question. My name is ***** ***** I am glad to assist you today.
I am very sorry about your issues. Are you using the Mac Mail app, the one with the postage stamp icon on the dock, to send and receive emails? Or are you using MS Outlook?
Also, what email account are you using in the email app?Please let me know by replying to me here so that I can help you further.