if its a Dr you have seen in the last year then you go to send a message. click the medical question. If I remember if click on anything else then it doesnt get you to the Dr. list. A Dr you have seen should be in the list to send message to. Then in the send body you have an option for an attachment. I usually put my name and birth date on my attachments if it is not on there. They can take 2 or 3 days to respond.

@nddavid, how frustrating. To get help with using the patient portal, I recommend contacting Mayo Clinic's Concierge Services. They can walk you through the process.
https://www.mayoclinic.org/patient-visitor-guide/minnesota/concierge-services
Call or email them
507-538-8438
concierge@mayo.edu