Just got a new Forerunner 945 and setup has gone fairly smoothly until this frustrating issue. During initial setup I had no problem, being able to setup connection to my home wifi through iPhone app. Today, I tried to setup Apple Music and as I went to download playlists onto the phone I was hit with a message "incorrect password" which was weird. I've spent the last hour trying to fix this, both on the phone directly and through Garmin Connect, and it's still the same problem. Running firmware 4.00, and confirmed that there's no problem with my wifi (all other devices in the home from TVs, laptops, tablets and phones are connected with no problem with either strength or consistency of signal. Only this damn Forerunner won't connect. I'm not getting an error message as some have mentioned in other posts, it's just saying "incorrect password". I'm absolutely convinced I've entered the correct password (hence the hour of troubleshooting), and it worked fine yesterday when I did the initial setup, so I'm not sure what's going on.
This is SO frustrating!!! I was so excited to take my new watch and go out for a run with music and without my phone, and I'm stuck dealing with this BS which just kills the joy of trying to enjoy my new toy...