Fasting Ramadan for thirty days continuously

Question:
What is the ruling on a group of people who fast Ramadan for thirty days continuously?

Answer:
This is not permissible. Fasting is based on the sighting of the crescent moon, .
The Prophet (peace and blessings be upon him) said, "Fast when you see it [the new moon] and break your fast when you see it [the new moon]." So he tied fasting to the sighting of the crescent moon and breaking the fast to the sighting of the crescent moon. The month may be thirty days or twenty-nine days, depending on the sighting of the crescent moon. If it is not seen on the night of the thirtieth, then if this is in Sha'ban, they will be in a state of not fasting the next day, because that is a day of doubt. But if this is at the end of Ramadan, they will fast on the thirtieth day, because the default is that Ramadan remains. In the first case, the default is that Sha'ban remains. Yes.