1. In the product description all the lines are getting merged in single line. It is not the case with kindle version. Kindle version works perfectly. But KDP paperback is not.
Please have a look at the product description here. You can see all lines are merged into one. https://www.amazon.com/dp/1522072942
2. I uploaded the new cover page image but it is not getting reflected in the product page. I have received email confirmation that my update is done. But still in the product page https://www.amazon.com/dp/1522072942 it is not reflected properly.
No need to post your link three times. You chose to use KDP-Print, so you have to live with its many glitches and bugs. If your updates don't appear on your sales page in two weeks, use the Contact Us button at the bottom of the page to tell the KDP boffins all your woes.