Your gateway constantly transacts with the blockchain. The transaction costs are called gas fees. Every beacon, witness or consensus event is processed 'on chain'. Also setting your location, activating your Crankk card or using the DEX are all handled by the Kadena blockchain. Such decentralised automation and transparency makes the Crankk network stand out among competitors.
Asking the blockchain to handle requests implies a processing cost: gas fees. These gas fees are paid by your gateway's wallet. If your gateway wallet runs too low on KDA to pay for gas fees, your gateway's actions will be rejected by the blockchain and your gateway will not be rewarded. Make sure to always have enough funds in your gateway wallet to pay for the gas fees. 1 KDA on chain 0 and 1 KDA on chain 19 of your gateway's wallet should last for months.