It sounds like moisture is trying to escape from the marble. This is a problem if a non breathable coating is placed on the marble. You will need to strip the coating off the floor and allow it to dry for several days. I would suggest polishing the marble rather than putting a coating back on it.
TIP Strip the coating with extreme caution. Avoid using highly alkaline strippers, since these stripers will deposit additional salts which can cause spalling of the stone.
Article ID: 486
Created: January 20, 2022
Last Updated: January 20, 2022
Author: Pam Freitag
Online URL: https://sr-manual.com/kb/article/i-just-looked-at-a-marble-floor-that-had-some-type-of-a-wax-on-it-there-appears-to-be-a-blotchy-appearance-as-if-something-is-coming-up-from-the-marble-and-just-under-neath-the-wax-what-is-this-486.html