How do I stop a sprite going through another?

Hi,

I'm working on a very simple (or should be) tank game, like the old Atari 2600 combat.

I have the tank rotating and moving slowly to follow the mouse pointer but its going through other sprites even though both sprites are set as "solid".

What am I doing wrong?

Your tank must have a behavior that interact with solids (8 Direction, bullet, etc).

https://www.scirra.com/manual/104/solid

Thanks