Erikahuer,
A couple questions for you to see if I can assist. When you say the button disappears from the page, do you on preview mode or in production? Is there a delay on the feedback button to make it only appear after a certain number of second or minutes? Have you tested this feature in different browsers and / or different devices? Sometimes I have found the error can be isolated to one specific browser and / or device. Sometimes I have also found that this is a caching issue and the majority of the time the general public at large won't have this issue if its something they are visiting as a course of business. Does that make sense? Ping me at ThomasW_IronMountain if you'd like.

ThomasW_IronMountain
It is in production
Not delay has been activated.
Only different browsers only in computer since we are using a QA environment.

Erika ,
Have you seen other issues before that existed in "prod" for the QA environment but did not then exist in Full Prod? Have you attempted to replicate the issue in another staging environment?
If you have the capability to look at this in full production from a developer point of view you may find that the issue does not persist or that the developers can identify what is causing the disappearance.