Your strava hadn't been bound with strava account.
The activities will not be able to be uploaded to strava,if your account hadn't been bound with your strava account.
In that case, you might
bind your strava account. if your account had been bound with a third-party account.
1. Bind strava account.
2. Delete the activities from iGPSPORT app.
3. Upload the activities to iGPSPORT APP again.
The binding with strava had been expired.
In that case, you will need to unbind your strava account and bind again.
Your strava account was bound with a third-party account.
In order to bind your strava account, you might try the following steps:
1. log into APP by choosing strava account from the third-party account.
2. Update the E-mail address to a correct one.(guide video)
If you still need assistance, you might contact with iGPSPORT support (firstname.lastname@example.org) with your APP ID for troubleshooting.