How does Fitbit Pay work on Ionic and the app?

[Waldip]

Yesterday I configured my Ionic and today I launched and configured Wallet (in the Android app).
I added the card to the wallet, set the PIN. Everything works fine on Ionic - I made the first payment.
After the transaction, a message from the Fitbit Pay application was displayed on the phone; after clicking on the message I was redirected to the Fitbit Pay login page (wallet tile). And this is ZONK ...
I don't have a login password. After clicking on the login window (the window is large, it takes more than 20 characters),only the numeric keypad is displayed. So I tried to enter the PIN, fixed to block the Ionic - it does not work.
With the help of the password manager, I entered the password for my Fitbic account - it does not work.
What should I enter in this window?

I can't take a screenshot from the app (screenshots are black), so I'm uploading a photo of my phone - this is the view when I click on the "wallet" tile.

Moderator Edit: Clarified subject

[Waldip]

Phew ... After a few hours it dawned on me (as opposed to the support staff: D)
In this window you must enter the PIN to unlock the PHONE.
I think programmers should enter this information above the password entry window; How can the user know that when logging into Fitbit Pay he should enter the password to unlock the phone?

[SilviaFitbit]

@Waldip Welcome to the Fitbit Community. Thank you for the details mentioned. 

I appreciate the troubleshooting performed and the time you took to share the solution found. Your feedback is appreciated, we're always striving to improve our services offered, the best place to make your voice heard is our Feature Suggestion board, those are reviewed by our team and the status will change depending on Fitbit plans. Also users have the opportunity to vote and comment on them to show their support. 

Have a good weekend.