They did. In any case, it takes about a week for a balloon to deflate.
This was all theater. The government has known about the balloon since it left China - which I think is why Blinken was suddenly going to China - and it was only found (visually, I believe) when it was about a week out over Montana. Then Blinken cancelled his meeting.
Somebody or even some agency saw the balloon and when it became public knowledge, the Biden regime had to react. But not before China got what it wanted and (probably) paid for. Look to see some US university involved in this.
Just my suspicions and speculation, not backed by insider knowledge...but that’s how I see it.
Also Russia was tracking it, and more importantly watching our reaction to it woth their spy satellites and agents on the ground.