Idealis - Regarding Rent Agreement Payment

So I just received my Document Verification response from Idealis and they've told to login to the Account and make the payment for first rent invoice and only then I can check the Rental Agreement and Sign it. Additionally, we have to do this in 48hrs.

Is this normal procedure? I'm just confused as they mentioned that I will have to pay the rent from the starting date (which is in Feb) but now they want me to pay it in the invoice. Also, the Website is not working (something like "Acceptance Environment is not active" pops up)