Error Code : 6000 - Business Validation Error:
We're sorry, we can't save the sales tax you're trying to set up right now. Please try again later. Error while updating contact in QuickBooks. Subscription period has ended or canceled or there was a billing problem : You can't add data to QuickBooks Online Plus because your trial or subscription period ended, you canceled your subscription, or there was a billing problem. To update your subscription, click the gear icon and view your account information.
This error typically occurs if your subscription has expired or canceled or if there is an issue with billing on your account.
Steps to resolve:
Step 1: Sign in to your QuickBooks Online company and Go to Settings ⚙ and select Subscriptions and Billing.
Step 2: Select Resubscribe> Select the New payment method (Credit/Debit Card or PayPal)> Enter the updated payment and billing information.
Step 3: Select Resubscribe.
Source: Refer to the article here for more information.
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