Does Your Yahoo Mail Reads Other Than What it was Intended?

About once a week when I open my Yahoo mail from a well known source it reads differently almost as if it is hijacked by someone else. This has happened with mail from at least 4 different sources. I would open the mail from my in box and it would read like a spam mail or from one of those Nigerian scammers. It would read as if it was from a whole different sender. Help guidelines say to copy headers and send them to the abuse center but when I go to open the headers I get a message saying that something is temporally wrong with that particular email. If I open the mail two or three more times it reverts to the original intended mail.

When I look at the help menus I don't see a provision for this. My computer shows clean with my AVG. So far this problem has happened once in a while from my friend's email. I know his mail is clean. It happened once from an ad from Etsy and that was the worst. That one was contorted to read like a Nigerian scam letter and the opening lines were that I should give my money to the "cause" and not to "those people" meaning Etsy. That letter was a little threatening. The rest were from a friend's email and those were contorted to read from a weight loss place and a singles club.

Before Yahoo mail went down a few weeks ago this happened 5 times. The mail came back up and the problem was gone for a couple of weeks until yesterday.

I don't think this is a fluke.

What do you think and do you know how to fix it? If you are from Yahoo admin this needs attention other than an automated response. I can't send these to spam or block them because they are received as legit emails from people and places I know.

Thanks

ps If you have the same problem as me let me know.