diff --git a/app/Api/V1/Controllers/Chart/AccountController.php b/app/Api/V1/Controllers/Chart/AccountController.php
index 4f7d27061e..10a40469fb 100644
--- a/app/Api/V1/Controllers/Chart/AccountController.php
+++ b/app/Api/V1/Controllers/Chart/AccountController.php
@@ -108,8 +108,8 @@ class AccountController extends Controller
                 'currency_code'           => $currency->code,
                 'currency_symbol'         => $currency->symbol,
                 'currency_decimal_places' => $currency->decimal_places,
-                'start_date'              => $start->format('Y-m-d'),
-                'end_date'                => $end->format('Y-m-d'),
+                'start_date'              => $start->toAtomString(),
+                'end_date'                => $end->toAtomString(),
                 'type'                    => 'line', // line, area or bar
                 'yAxisID'                 => 0, // 0, 1, 2
                 'entries'                 => [],
@@ -120,7 +120,7 @@ class AccountController extends Controller
             $previous     = round((float)array_values($range)[0], 12);
             while ($currentStart <= $end) {
                 $format   = $currentStart->format('Y-m-d');
-                $label    = $currentStart->format('Y-m-d');
+                $label    = $currentStart->toAtomString();
                 $balance  = array_key_exists($format, $range) ? round((float)$range[$format], 12) : $previous;
                 $previous = $balance;
                 $currentStart->addDay();