It is a Monterey oak. It generally does well, even in terrible soils. Looks like either too much water or not enough. It could be root flare too deep as well, or root bound when planting. If the root flare is not below the ground, and the roots have taken hold firm (pushing trunk does not move rootball), and there aren’t any holes / damage to the bark on the trunk, it should heal and do fine for you if you take care of it properly, meaning mulch 3 inches deep for 5 foot free of grass or weeds, and water to the drip line only when dry. It doesn’t like water every day… Use a slow release fertilizer next februaryish as new leaves push and you should see an explosion of growth!