Connection over the Bluetooth

I have a scooter that connects to my phone using Bluetooth and it sends an array of data, the phone connects with the scooter without a password but it sends a handshake message to start getting the data to send back, it sends the handshake just once and after that, it gets the data every second or less.
how can I make Realdash send the handshake message?
Thanks for helping out

I would need to know a bit more about the protocol your scooter is communicating. Give an example of the Data Flow.

The data received is bites array
(byte[]) bytearray
in android java code, and to get the speed for example
speed = bytearray[20]

the handshake message is a byte array sent to the Bluetooth like this:

so the app is getting raw byte array data and sends the handshake message as byte array too.

So what are the contents and lengths of the byte array?

There is currently no way that you can add completely new protocol to RealDash without our help. If your scooter is somewhat popular model, I can add a support for it, but to do that, I need a complete spec of the data.