That happened to me once. Here's how I fixed it. You know where you can type in your password twice to change it? Do that (but type your current password in both the first and second space. The first space should be yellow). Then, before saving changes, remove your signature. Now save changes. Your signature should be removed and your password "changed" (changed from, let's say, "router" to "router", so your password will actually stay the same). Hope this helps!
