Landlord not making a repair!!!!!

We moved into this house a few months ago, on the day of viewing, we noticed that the big part of the glass wardrobe in one of the two rooms was broken(the lower part)... I pointed this out and the lady told me that it will definitely be fixed before I moved in. When signing the tenancy agreement, it was boldly stated by the letting agents that they will fix the broken wardrobe before we move in. We moved in and the wardrobe wasn’t fixed! Seven months later, they still haven’t fixed or replaced it. This room is my baby’s nursery and my baby now crawls about. I have sent countless of emails and put calls through to the letting agents, but still nothing has been done!! Has anyone experienced something like this before? What line of action can I take? This pose a health and safety risk to a baby having a broken wardrobe in her nursery! Kindly advise anyone please? P.s; we live in the UK. 🇬🇧