Garmin RV 770 LMT-S

I cannot find any option to change the female voice to a male voice. The only language options I can find is to change languages, not voices. When I connect Garmin Express and choose the Store and click on Vehicles & Voices I only get a popup that says, "Feature Not Available. Vehicles & Voices is no longe available. You can keep any custom vehicles and voices you have installed on your device, but you won't be able to use Express to install new ones or remove them."

Does anyone know where I could get different voices (i.e., a male voice) for the RV 770 and then how to install them? Thanks.