diff --git a/library/X509/Job.php b/library/X509/Job.php
index 1e0b3f73..e800a8ee 100644
--- a/library/X509/Job.php
+++ b/library/X509/Job.php
@@ -723,7 +723,7 @@ protected function processChain($target, $chain)
                     ->filter(Filter::equal('self_signed', true))
                     ->first();
 
-                if ($rootCa && $rootCa->id !== $lastCertInfo[0]) {
+                if ($rootCa && $rootCa->id !== (int) $lastCertInfo[0]) {
                     $this->db->update(
                         'x509_certificate_chain',
                         ['length' => count($chain) + 1],