Error 123:259a6556:13acala0

Hello guys, i installed some mods, in particular mods to customize the characters and some for the house. When i enter the game and create the character there are no problems, but when i want to enter the city it gives me this error "The game loading failed. Error code: 123:259a6556:13acala0. it is advisable to restart the game". i searched online but i can't find this specific error. Can someone help me please? Thank you