[A930Rocket]

I’m no engineer, but think a couple options are to lift the block up by lifting the footer up, assuming it has a footer.

Used the existing footer, replace the block as needed, and core fill the cells with a grout mix.

Any way to find out if this is something that happened over time or something bumped it from the inside, as mentioned?

Once you repair it, you can get small plastic gauges that adhere to either side of the crack and it measures the gap over time.