But no one has ever said vaccinations completely prevent someone from getting Covid. However, they reduce the risk and, should you get it, they reduce the likelihood of someone having to be hospitalised or have serious complications, etc.
A friend of my mum's who's in her late 70s and doesn't have the best health recently contracted Covid but had no symptoms. It was only picked up because she was due an operation so she had to have a PCR test before being admitted to hospital. She's triple jabbed, having had her booster vaccine a few weeks ago. Now of course no one can categorically prove her vaccinations stopped her getting any symptoms, but it's certainly likely that they did.