Watertank on Car wont let me pour water in it

I have a jerrycan with clean water and want to put it into my new vehicle i have a watertank installed when i examine the vehicle hover over the place where the tank is and want refill but its not working nothing happens the vehicle isnt broken or anything is that a bug or im doing something wrong??

Press “f” ?

Are you holding the jerrycan?

i did push f… but on restarting the game the next day it worked still weird…