You’ve got a few solid options:
- Log into your router (check the sticker or use 192.168.0.1 or 192.168.1.1 in your browser)
- Look for “Connected Devices” or “Device List”
- Identify the unwanted device (by name, MAC address, or what’s unfamiliar)
- Either block it directly or change your WiFi password and reconnect only your own devices
- Pro tip: enable MAC address filtering or hide your SSID if you want to lock things down further