Are these e-mails you are receiving solely spam?
Have you marked these unwanted e-mails as spam and they are finding their way into your inbox with different sender addresses?
When you spoke to Yahoo what did they mention to do?
Have you attempted to block the e-mail addresses? If these are all coming from one e-mail address this would be a possible solution. Or are the spammers using different e-mail addresses each piece of spam mail?
If Yahoo has failed to correct the issue, I would suggest forwarding your legitimate mail to another server- e.g.***@******.***, or outlook.com and keep the yahoo domain open. This is a short term fix, there are malicious programs that once they get your address they will flood your e-mail with spam and there is unfortunately no real way to stop the flood. This happened to me a couple years ago and the forwarding technique has worked well. This is in the interim mind you, I would continue to work with yahoo and follow up with them if you have opened a ticket regarding your mail.
You're very welcome! I am sorry this is happening to you- it really is the pits. I will mark this issue as closed.
I hope all works out for you, thank you for using Just Answer.