Check that the password you entered is still current. Make sure that you are not using the password for your SIM card, Google account, music service or another account. Teufel Streaming requires the password for your home WiFi. This is sometimes also called the "network key".
A tip I: You'll often find your WiFi password/network key on the back of your WiFi router. As long as this password has not been changed, it should still be valid.
Tip II: The autocorrect function in your smart device may be changing the characters you enter. We, therefore, recommend switching off this auto-correct function.