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20 September 2019
Emily, Customer Service
Oh no, it sounds like your T. Rex is looking a little less than ferocious!
It sounds like you've actually got the legs in the holes that are meant for the arms. The leg holes will have ridges around them, which gives the dino enough friction to stand upright. The arm holes will be smoother. Try swapping the arms and legs and you should have much better results.
If you need a hand making sure everything's A-Okay, you can always get in touch at www.LEGO.build/Service.