Disabling credit at the Contract level is done in the Contract window.
From the Main Menu, Go to Advertisers - > Contracts -> Contracts. Click on the Contract Name to open the Contract Window.
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From the Contract's window toolbar. Click on Contract Credit -> Disable Credit...
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You need to confirm that you're disabling credit at the Contract Level.
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Note:
- Disabling credit does not mean the Contract does not have credit to purchase leads or calls.
- Disabling credit will not issue refund to the Advertiser credit card.