How to handle The tax calculation call to Zuora Connect returned the following error: unknown error.
When previewing a subscription, you might get a message "The tax calculation call to Zuora Connect returned the following error: unknown error."
The subscription preview must finish within 120 seconds. If this is a very large subscription and the preview periods is long, the number of line items will be high. When tax app is used to calculate the tax, zuora will send the tax calculation request to tax vendor. Tax vendor might not send the response in time and cause the subscription preview issue.
A single tax calculation request sent to a tax connector app can have a maximum of 15,000 taxable items. If a tax calculation request contains more than 15,000 taxable items and is sent to a tax connector app, the request will fail and an error message will be returned. https://knowledgecenter.zuora.com/Zuora_Central/Billing_and_Payments/J_Billing_Operations/L_Taxes/Co...
1. Shorten the preview billing periods. By default, it is 3 billing periods. That will make the number of line items in the request smaller too.
2. Separate the big subscriptions into smaller ones, so when preview, the number of line items in the preview request will be much smaller.