Problem with scene switching

So im currently developing a single AR application. Im just doing the UI for now and wanted to separate all the menus and their transitions in one scene and the AR component (using Vuforia) in another.

Im doing the UI using an asset called Dotween and it works very good. In the AR scene i put a test button just for when the user decides to go back to the UI menus after having used the camera but when i go back (with a standard canvas button) my scene looks blank. I dont have the skybox enabled, just plain white so im curious to know how to fix this problem.

Im attaching the two scripts:
-Test Script im only using to try to go back to the other scene after i push a button.
-UIManager is the script im using with Dotween to manage different canvas and transitions when buttons around the UI are pushed.

Im sorry for the bad coding (its my first app) but most of the functions of it are just for moving UI components and are in spanish and english notation cause im using two different languages.


Thanks in advance to anyone that can help ... ive tried :
- LoadScene (name)
- LoadScene with the build index
- Saving Playerpref