What are the chances of this occurring?

Hi - A peculiar thing has happened to me: While visiting the UK, I recently opened an app for a Loaf wallet on my Iphone - I was given a 12-word seed to copy down, which I did - i then remembered that I recognised many of the seed words - I consulted some old files for an old LTC wallet which I had used on my PC in Thailand - the seed is exactly the same!!! How is this possible?