Need to stop "signingmessage" after it reaches a signing number, how to do an airdrop

I have a REACT app
that has a MetaMask “signingMessage” that connects to my Moralis DB.
The signing message allows me to collect the wallet address of the user that signed the message.
I will be using the wallet addresses for an Airdrop.
After the Airdrop quantity is subtracted the ERC1155 will subtract the Airdrop quantity from the total quantity.
The total quantity left will then be for sale.

How can I stop the signing message after the Airdrop quantity has been met?
How can I then use the “account” table in the Moralis DB to distribute the Airdrop?
What would this code look like?

You should handle some logic in the smart contract