The password must contain letters, numbers, and other special symbols
sorry this is way out of date

see for example here: https://www.bbc.co.uk/news/technology-40875534

as far as a computer is concerned a character is a character is character, they are all the same and it makes no difference at all to a hacking program [a jumble of so-called special characters might make it less easy for someone looking over your shoulder, but you are not going to let that happen are you?]

as is sadly the case a lot of industry lags behind on this still

you need long passwords that are easy to remember and at the very least 24 characters; twelve is too short, what you need are as high a number of permutions as possible

foraging ducks lit by moonlight glide between reeds under the sargasso sea

and as the referrenced article states - a reputable password manager is what you should be aiming for