Automatically translate this page?

How to send messages to telematics hub from my custom solution via MQTT?

Using MQTT to put the data into your flespi channel.

MQTT usage assumes that you have a good technical background. This may be written on first demand. However, we have everything explained here:

See also
Obtain telematics data from Jimi Concox devices via API in 5 easy steps.
Using flespi plugins to pack together the data coming from two or more related devices.