Help & troubleshooting for channels on your Roku device, including adding/removing channels, logging in to, authenticating, or activating a channel, channel-specific playback issues, assistance contacting channel publishers to report issues, and adjusting channel-specific settings.
The 3920 is a Roku Premier released in 2018. The hardware is capable of running Prime Video.
Amazon has made Prime Video available in Mexico, but you can only stream when you are located in the same country in which your Prime Video account is based. If your account is based in Mexico you should be okay. If you are just visiting Mexico with an account based elsewhere, you may not be able to stream Prime Video.
Roku Streaming Stick +, 3810X, Ser YH0059427035, wifi LivRm - Samsung UN55ES6100
Roku Streaming Stick, 3600X, Ser 5S56D8240827, wifi BedRm - JVC EM37T
Roku 3, 4200X, Ser 4124C7087583, wifi GstRm - Sanyo DP26640