error while npm start - Undefined variable: "$grid-row-columns" in...

I am getting ERROR in

./src/styles/theme/bootstrap.scss (./node_modules/@angular-devkit/build-angular/src/angular-cli-files/plugins/raw-css-loader.js!./node_modules/postcss-loader/src??embedded!./node_modules/sass-loader/lib/loader.js??ref--14-3!./src/styles/theme/bootstrap.scss)
Module build failed (from ./node_modules/sass-loader/lib/loader.js):


undefined ^Undefined variable:

"$grid-row-columns".
in {path}\node_modules\bootstrap\scss\mixins\_grid-framework.scss (line 37, column 30)

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