Can't log in to edit ad

I placed an ad:

Then I sold the phone, so I edited the ad as “over, done, finito” and that was that. Until this morning, when I had an inquiry about the phone. I followed the link in the e-mail and saw that the red header saying the ad was over was gone. So, I logged in to edit the ad, clicked on the “Edit ad(s)” button, and was promptly returned to the login page. Checked password to make sure it was correct, and it was. Tried again, same result.

Anyone else having this problem?

EDIT: I went back today and tried disabling my Norton Internet Security after logging in, and that worked. I don’t know why I never had to do that in the past, but something seems to have been changed, and now I can’t stay logged in to Taiwanted with security on. I have it set to accept cookies from that website, so not sure what the problem is. I have no trouble staying logged in to Forumosa.