Special Bingo Chapter is a time limited event and if the limited time is over, it is impossible to play it again.
Regular Bingo Chapter is also a time limited event but when the next Regular Bingo event starts, you can complete the Regular Bingo Chapters that you could not finish previously.
Please take note that the completion Reward of the previous Bingo Chapters will not be the same from the initial Reward when it opened again!
For example, if you were not able to complete Bingo Chapter 2 and the event period ended, you will be able to continue and complete Bingo Chapter 2 when Bingo Chapter 3 opens but the initial Reward for Bingo Chapter 2 will not be the same when Bingo Chapter 3 opens.