Exide battery of my new 4 months bike is not working properly. Self is not working. Should I ask forreplacement or repair?

For this, we would suggest you to visit the nearest service center and get it checked if there is any issue with the battery then they will replace it or if the problem is with the charging then they will repair it. You can click on the following link to see the details of the nearest service centre and selecting your city accordingly - Service centre.