Why Customer print format broken in ERPNEXT 13?

I am using ERPNEXT13
I had couple of print format in my old erpnext 6 and after migration I see that printformat not working.
bootstrap class row, col-xs-6 not working in pdf. Table cell doesn’t have any border and so many issues.

Even I am not sure which bootstrap version is running in my erp.

find . -name bootstrap.css | xargs grep Bootstrap

./apps/frappe/node_modules/bootstrap/dist/css/bootstrap.css: * Bootstrap v4.5.0 (https://getbootstrap.com/)

./apps/frappe/node_modules/bootstrap/dist/css/bootstrap.css: * Copyright 2011-2020 The Bootstrap Authors

./apps/frappe/frappe/public/css/bootstrap.css: * Bootstrap v3.3.1 (http://getbootstrap.com)

I can see a list of bootstrap here.

Please someone help me.

The older version of bootstrap use grid layout and newer version uses flexbox.

If you could post the code here it might help