Hi @SarahT3 . This message is showing because the app is calling an unsupported or unspecified API version OR because its calling some deprecated or about to be deprecated resources. You can use this REST call to check if your making calls to deprecated resources. https://shopify.dev/api/admin-rest/unstable/resources/deprecated-api-calls, and you can also check with our Partner Support team with your API client id/ app details as they can look on our internal db to see if your calling deprecated resources still as well. Hope this helps.