The check in counters is reset on 1st of every month. The accumulative day will recount.
The interface is as follow:
A red circle will appear on the date after you check in successfully every day.
If you don’t reach the standard of bonus, you can click to have a check. If you have acquired the bonus, the button will turn to gray and change to “have acquired”.
The default is showing the check in bonus that you will acquire.