Short answer: this can happen because of coverage changes, exhausted data, expired validity, temporary network issues, or changed phone settings.
Check these
- Check remaining data and validity on your 4S service page.
- Restart your phone.
- Confirm the 4S eSIM label is still selected for mobile data.
- Turn data roaming on for that line.
- Try LTE/4G instead of 5G.
- For Android, confirm APN is still selected.
Need help?
Contact 4S support through support@4s.net, a Zendesk support ticket, or Zendesk live chat. Do not reply to hi@4s.net; it is an automatic order and installation email sender.
When contacting support, include your order email, ICCID if available, destination, phone model, and screenshots of the error or SIM/eSIM settings page.