diff --git a/static/src/js/operation_chart.js b/static/src/js/operation_chart.js
index 950e164abb0d32f296ffaccc3f0783a8279fa0d5..872623e7c0fe1263c1c4787e4857ffe13160fe82 100644
--- a/static/src/js/operation_chart.js
+++ b/static/src/js/operation_chart.js
@@ -47,10 +47,14 @@ odoo.define("oacc_portal_overview_cdc.operation_chart", function (require) {
             this.chartData = null;
         },
 
-        /**
-         * @override
-         */
-        willStart: function () {
+        willStart: async function () {
+            await loadJS("/web/static/lib/Chart/Chart.js");
+            await loadJS(
+                "/oacc_portal_overview_cdc/static/src/js/lib/chartjs-plugin-datalabels.min.js"
+            );
+            await loadJS(
+                "/oacc_portal_overview_cdc/static/lib/daterangepicker/daterangepicker.js"
+            );
             var self = this;
             var def = this._rpc({
                 model: "acc.operation",
@@ -60,17 +64,6 @@ odoo.define("oacc_portal_overview_cdc.operation_chart", function (require) {
                 self.minDate = data.date_min;
                 self.maxDate = data.date_max;
             });
-            return Promise.all([this._super.apply(this, arguments), def]);
-        },
-
-        willStart: async function () {
-            await loadJS("/web/static/lib/Chart/Chart.js");
-            await loadJS(
-                "/oacc_portal_overview_cdc/static/src/js/lib/chartjs-plugin-datalabels.min.js"
-            );
-            await loadJS(
-                "/oacc_portal_overview_cdc/static/lib/daterangepicker/daterangepicker.js"
-            );
         },
 
         /**
@@ -682,16 +675,16 @@ odoo.define("oacc_portal_overview_cdc.operation_chart", function (require) {
 
             // Disable buttons if first or last date
             if (
-                moment(this.last_day, "dd/mm/yyyy") >=
-                moment(this.maxDate, "dd/mm/yyyy")
+                moment(this.last_day, "DD/MM/YYYY") >=
+                moment(this.maxDate, "DD/MM/YYYY")
             ) {
                 $('button[id="next-period"]').prop("disabled", true);
             } else {
                 $('button[id="next-period"]').prop("disabled", false);
             }
             if (
-                moment(this.first_day, "dd/mm/yyyy") <=
-                moment(this.minDate, "dd/mm/yyyy")
+                moment(this.first_day, "DD/MM/YYYY") <=
+                moment(this.minDate, "DD/MM/YYYY")
             ) {
                 $('button[id="previous-period"]').prop("disabled", true);
             } else {