MuseScore 2 --> 3

Following its installment, I launched MuseScore 3 and opened a Work-In-Progress file from MuseScore 2. Other than the fact that elements, such as crescendos, reset themselves, there is no audio when playing back the score, or clicking certain notes MDL or not.

Currently I'm running the most current version of MuseScore on a Windows 10 laptop.
How do I regain sound? I already tried going to Synthezier -> Fluid.