Welcome to GoY, Kbkb!
It actually looks rather sickly to me. Judging by the symptoms, it could be suffering from lack of nitrogen, drought, and/or excessively acid soil. Certain physical problems can also cause those symptoms, such as being planted too deep or strimmer damage to the trunk. Scale infestation could also do that, but they are pretty obvious: resinous or woolly bumps on the twigs and leaf veins, and sticky honeydew coating the lower leaves.
To decide what the problems might be requires a close inspection of the base of the trunk and the foliage and twigs, first. If that turns up nothing, a soil analysis is probably in order.
Good luck!

welcome to GoY from me too,
the standard part ie the 'trunk' doesn't get any taller but the 'head' of leaves will continue to grow.

But I agree it doesn't look too happy.

Thank you both for taking the time to reply. That photo is actually from last year when we planted it. It's actually a lot healthier now. I'll try to attach a photo.

https://photos.app.goo.gl/Sa8Lo3JB4CbSKk9M7

Sorry, Kbkb, but I can't access that photo. I haven't tried it myself, but supposedly you can change the photo in the question.

It certainly looks healthy now. As Seaburn says it is only the head that keeps growing. As a theory I suppose you could raise the crown by cutting off the lower branches of the head and incorporating the new growth into a new head, thus making it taller. More knowledgeable advice needed before you act on that though!