Tip Calculator Solution HTML | CSS | JS

The only hard part in this project was the JScript code for me. Unlike my Sunnyside Agency Landing page, this page works well even for small screens. HELP/Solution Request: If you visit my page you can calculate the tip no issues but I if you have the same bill amt. and number of persons, once you click the tip percentage/ type in the custom percentage it gives the result but after the solution is outputted and I want to see the result with another percentage but same parameters, it doesn't respond. You'll have to reset and type again. If you've figured out the solution of it please do share it with me.