Problems with scrap.tf

[Rei.quaker]

Hello hello steam users
I'm trying to get some weapons that I don't have in tf2 by trading them for others that I have repeated.
The problem is that when trying to trade in scrap.tf I get this:

Trade Error
Unfortunately, this trade would have resulted in a trade hold. You need to have a Mobile Authenticator on your account for at least seven days for trade holds to not occur.

And in the button below I get:

Click here for a step-by-step guide to fix this

When I click it takes me to an error:

Error 1033 Ray ID: 8beb89bd2cd8c817
Argo Tunnel error

Does anyone know how to solve this? or why does it happen? thanks a lot...
I already have my Steam account linked to my phone number...

[PokerDude]

How about you stop buying from pdf files

[PokerDude]

Your problems will be solved I promise

[druuu]

Enable steam mobile authenticator within the app itself. Having a phone number and app isn't enough.