diff --git a/index.js b/index.js
index 62aaa07bc2588d55d04b9904ccb37f73044a7e2b..49509c12606063cb54f8f0db25e9379a2852484f 100644
--- a/index.js
+++ b/index.js
@@ -132,9 +132,9 @@ async function start(fields, cozyParameters, doRetry = true) {
   const accountId = getAccountId()
   try {
     log('info', 'Fields')
-    log('info', fields)
+    log('info', JSON.stringify(fields))
     log('info', 'account')
-    log('info', this._account)
+    log('info', JSON.stringify(this._account))
     const { access_token } = fields
     let usage_point_id = ''
     if (