Invalid Avalara Credentials
Recurly validates your Avalara credentials whenever they are added or edited to keep you from saving invalid credentials. Your Avalara credentials will become invalid in Recurly if your Avalara account becomes "Inactive", meaning your development or production Avalara account expired, or if Avalara is having authentication service issues.
When your credentials are determined to be invalid, Recurly will send an email to your Technical Contact. If you have not specified a Technical Contact, the email will go to your Billing Contact. If you have not specified a Billing Contact, the email will go to the first user on the account with Admin user rights. This email will only be sent once at the time the credentials become invalid.
While your credentials are invalid, the mode of your site will determine invoicing.
If your site is in production mode, Recurly will continue to send invoices to your Avalara account. By default, new sign-ups and purchases will be blocked due to the authentication error Avalara returns. If you know your credentials are correct and you suspect that Avalara is having authentication issues, you can disable the block on new sign-ups and purchases and allow those invoices to go through without tax until Recurly gets a successful response from Avalara. To disable the block, go to Configuration > Taxes > Tax Settings > deselect "Require tax response from tax service" and save the page. Learn more about this option.
Whether you block or don't block new sign-ups and purchases due to an error, as soon as Recurly gets a successful response from Avalara on an invoice, Recurly will reset your Avalara credentials to be valid again. Note that when credentials are invalid, renewals will always go through and generate an invoice without tax. Recurly will not stall the renewal and retry. Recurly does not retry the subscription because if the Avalara account has truly expired, which is the primary scenario, it would stall subscription renewals across your site for potentially a long amount of time.
If your site is in sandbox mode, meaning you are testing Avalara, Recurly will ignore your credentials and stop sending requests to Avalara when an invoice is created. This means each invoice will not have tax until you fix your credentials.