Fitbit 403 error code when setting up Versa or Inspire

[FitSA]

I have a fitbit versa and fitbit inspire. With both I can not set up the devices. I tried on 3 different phones(iphone, samsung, cubot) cant even use one of this watches to see the time. On my Iphone i get an error 304 message, samsung and cubot devices:” fitbit.com is down for maintenance” Please help! I really love my fitbit watch! Would be amazing if I can actually use it.

Moderator edit: subject for clarity 

[LiliyaFitbit]

Welcome to the Fitbit Community, @FitSA.

Thanks for the details shared in your post. I understand how you are feeling and appreciate your efforts. I recommend doing the following:

1. Make sure your Fitbit app is updated to the latest version: How do I update the Fitbit app?

2. Restart your router.

3. If the issue persists, try turning off WiFi on your phone and using your cellular data to set up: How do I set up a replacement device or add a second device to my account?

Note that you can't connect multiple devices that use the Fitbit App Gallery to one account. For Fitbit Charge 3, Fitbit Charge 4, Fitbit Ionic, Fitbit Inspire series, Fitbit Luxe, Fitbit Sense, and Fitbit Versa series, only connect one of these devices to your account at a time. For more information, see Can I use more than one Fitbit device with the same account? 

By the way, I've moved your post to the iOS App board so we can keep our forums organized.

Hope this helps.