There is no danger in not reporting the loss, because the card is under the control of the bank.

But you should contact the bank in time, because the custody of ATM cards has a time limit, usually one week to one month, after which the cards will be destroyed.

If the card is swallowed by the ATM of your bank, just take your ID card to get it, but if it is swallowed by the ATM of another bank, you have to go to the issuing bank to issue a certificate to prove that the card is yours.

The card is not dangerous. Don't worry, the card is stuck in the machine. Only when the staff opens the box can they get it. No one else can do anything about it.