my ex is stalking me

long story short i broke up wit my controlling toxic ex a year ago and changed my number because he kept blowing me up 24/7 day and night even after i block him. he would just keep making numbers on a free texting app bugging tf outta me and some how he found my new number and is now blowing me up non stop again even though he knows i have a man with a baby. wtf should i do🤦🏽‍♀️ no matter how many times i change my number and tell him to leave me alone he just won’t listen and stop