This problem has been reported on and off for URLs in ACF fields and it can happen with text fields as well as URL fields, but has never been resolved because in testing no one has ever been able to reliably recreate the issue.
The best that can be said is that it may have something to do with server/php settings on your live server. To debug this you need to figure out where and why the redirect to a bad page is happening and the only way to do this would be follow the save process of the options page through all of the acf code and figure out where the URL of the ACF field is effecting the URL that WP is trying to redirect to.
What we need is for someone that has to ability to do the debugging to also be able to reliably recreate the issue.
