Unable to upgrade the Express PayPal with this version

[pchiranjeet]

As we receive notification to upgrade our express PayPal integration to new approach as the old version is expiring soon.

We connected with Adyen technical team and found that the API version 69 which is our current version supports the new approach of Express Paypal.
But while trying to implement the changes to get the pspReference back with /payments API response, found that there is no option to pass "express" as payment Subtype with PayPalDetails request object.

We tried to extend the PayPalDetails class but it didn't worked.

code snippet :

SubtypeEnum does not have any value as EXPRESS,
its only having 2 values SDK("sdk") REDIRECT("redirect")

PayPalDetails payPalDetails = new PayPalDetails()
.subtype(PayPalDetails.SubtypeEnum.SDK) // This was set for regular PayPal and we have set it to"express" for Express PayPal
.type(PayPalDetails.TypeEnum.PAYPAL);

Reference class we are using :
PayPalDetails.class [SubtypeEnum was declared inside this class]
Checkout.class

Could you please share the steps we need to follow to get the pspReference back in /payments API response with our current API v69 ?

Our Package Details:

API Version:  69
Hybris Package: 11.2.0
Java Library : v18.1.3
Front End library : Adyen Web (https://www.npmjs.com/package/@adyen/adyen-web) @adyen/adyen-web@6.6.0