diff --git a/src/reverseproxy.js b/src/reverseproxy.js
index 1da2e60e3..2b834b3c2 100644
--- a/src/reverseproxy.js
+++ b/src/reverseproxy.js
@@ -412,7 +412,7 @@ function ensureCertificate(vhost, domain, auditSource, callback) {
             return callback(null, getFallbackCertificatePathSync(domain), { renewed: false });
         }
 
-        const { acmeApi, apiOptions } = getAcmeApi(domainObject);
+        const { acmeApi, apiOptions } = await getAcmeApi(domainObject);
         let notAfter = null;
 
         const [, currentBundle] = await safe(checkAcmeCertificate(vhost, domainObject));