I am trying to implement the date picker dialog but the dialog appears with just a single date and show rest of the date as blank what could be the reason?
This is definitely a Theme issue. The selected date is visible because of the contrast in text color and circle color. You can refer this link for understanding the anatomy of the Date Picker theme by the Material design guideline.
https://material.io/components/date-pickers#theming
Refer this answer for understanding which colors to use.
https://stackoverflow.com/a/29014475/4491971
You can use these attributes to change the colors via style
dayOfWeekBackground
dayOfWeekTextAppearance
headerMonthTextAppearance
headerDayOfMonthTextAppearance
headerYearTextAppearance
headerSelectedTextColor
yearListItemTextAppearance
yearListSelectorColor
calendarTextColor
calendarSelectedTextColor
If you share the current style and the code snippet, we can refine the answer more.