Hi simpmg,
My name is Melissa and I am the Social Media Manager here at iPage. We've been keeping an eye out on the forums to see about assisting customers wherever we can.
It sounds like you already have this issue diagnosed and know that you'll need to re-install the theme at a minimum. Please make sure that all account and application related passwords are updated as a precaution. Also, I would not rule out plugins unless you have tested by disabling all of them and the issue persists.
Kind regards,
Melissa
Social Media Manager