Hi,
As the message we display on your backend says, the old PayPal API which is implemented by the old PayPal plugin will be discontinued soon by PayPal. There is no date set yet, but it's more than 15 years old.
PayPal reached to us asking us to promote switching to the new PayPal Checkout in advance of that change in order to smooth things out for merchants.
Other than that, the new PayPal API has a nicer user interface for customers, with more payment methods available to them, like bancontact or Pay Later. These can increase your transformation (more sales for the same amount of users). So we think it's a win-win situation for everyone.
Normally, when you use the "Conntect to Checkout" button, there are no questions. You enter your PayPal email address and password, you click on the "Agree and connect" button and that's it.
What you're describing is the procedure when you create a new PayPal account through there.
Note that PayPal uses different accounts for their sandbox and live environments. So if you activate the sandbox setting and try to connect, if you provide your live account email address, PayPal won't see your account for that email address on their sandbox environment and you'll be led through the registration workflow of a new PayPal sandbox account.
I suppose you must have done something like this.
Also, alternatively to the "Connect to Checkout" button, you can manually retreive your Client ID and Client secret from your PayPal account to enter them in the payment method:
www.appinvoice.com/en/s/documentation/ho...id-and-secret-key-22
That way, you won't need to go through the "Connect to Checkout" button.
However, if you provide the Client ID and Client secret from a live account with the Sandbox option activated, it won't let you go through the payment at the end of the Checkout.