diff --git a/htdocs/compta/bank/line.php b/htdocs/compta/bank/line.php
index b0113149146..3661eec8e8e 100644
--- a/htdocs/compta/bank/line.php
+++ b/htdocs/compta/bank/line.php
@@ -125,7 +125,11 @@ if ($user->rights->banque->modifier && $action == "update") {
 	$error = 0;
 
 	$acline = new AccountLine($db);
-	$acline->fetch($rowid);
+	$result = $acline->fetch($rowid);
+	if ($result <= 0) {
+		dol_syslog('Failed to read bank line with id '.$rowid, LOG_WARNING);	// This happens due to old bug that has set fk_account to null.
+		$acline->id = $rowid;
+	}
 
 	$acsource = new Account($db);
 	$acsource->fetch($accountoldid);