Anybody know what this means?

[Cb83]

So this morning had these two messages come up after an ad blue 1400 mile left warning, can anyone shed any light on it? Seems to me to be a minimum and maximum weight?!

 

[Pauly]

Yeah its telling to refill with between 1.75 and 2.5 gallons of adblue

 

[Cb83]

Ohhh it's gallons, doh! Thanks for that, couldn't get grams out of my head.

 

[Loz]

If you temporarily change your units to metric, it will swap to litres.
please don’t overfill and then turn on the ignition and leave it at least 30 seconds to register before starting.