App Reject many times

Hello, I have develop a app but continue to reject for 2 problems from resolve:

For GUIDELINES 3.1.1.: I don't know how i can resolve, because there are more apps that is paymant using browser on app without use in-app purchase, example the apps SUPERENALOTTO when I pay, open a window browser with type of payments (especially out the app), the app ENI PLENITUDE when there is a bill to pay, can pay with Apple Pay on app but how can I specify the price on in-app purchase if the price is not fixed but occurs based on the cost of the bill. On in-app purchase there are the price that I have to insert from $0.99 to up. Please can you help me? Because, yesterday I have change on app the payment on browser but they rejected it anyway.

For GUIDELINES 5.1.1: There are too every apps that can registered without specifying or explaining what registration is for, example the apps BADOO and LOVOO and NETFLIX there are only ACCESS, REGISTERED and PASSWORD DISMISSED...Can you help me with this too? Can I see a specific example? A screenshot?

I've been studying and updating/editing for many days but they rejected me 10 times Thank you very much.

It doesn't matter what other apps do. You need to do what Apple tells YOU to do. Citing other apps will not help.

how can I specify the price on in-app purchase if the price is not fixed

Fix the price. You need to make your business model match what Apple supports. You cannot make Apple change to suit what you want to do!

Hello, thank you for the answer but Forgive me, I still don't understand why I repeat them, on the app there are events that have their own price, it's not precise or fixed so how can I specify the price on in-app purchases? Unfortunately I look at all the apps they have developed, it is to understand how they did it and why they were published!? The SuperEnalotto app has a payment service not including Apple Pay but PayPal, Strike, Stripe, etc and as specified on in-app purchases and it is outside the app, this is what makes me doubt... but for Is there a more precise and easier to understand page? like on YouTube or an example?

App Reject many times
 
 
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