Apple pay payment processing certificate renewal related queries?

I have one existing iOS application in which apple pay is integrated. This application is live on app store. Now its apple payment processing certificate is about to expire.

I have following questions

1)As per docs, i can not renew it, i have to create the new certificate. is this correct? 2)Can i use same merchant id which was used with previous certificate? 3)If i create new certificate, will old certificate be stopped working?

4. As per my understanding for creating CSR there are 2 options

1)You can create it from the keychain if you are processing the payment 2)or you can get it from the your payment service provider

This url describes the steps to create CSR and payment processing certificate https://help.apple.com/developer-account/#/devb2e62b839?sub=devf31990e3f

Here we just need to select the CSR, it can either be generated by you or provided by the payment provider, so there is no option to activate the CSR, so if i generate new certificate now, which certificate will be considered?

Any help would be appreciated.

1. From my understanding, yes, you will need to create a new certificate.
2. Yes, you should be able to use the same merchant ID (assuming nothing has changed on the merchant side.)
3. EDIT: According to Apple, once you create the new CSR, you'll need to manually activate it in the portal. Also, it is noted that you don't need to update your app in the App Store for this either. Hope this helps.

EDIT: This link from PayPal Developer gives a step by step guide to do it. https://developer.paypal.com/braintree/docs/guides/apple-pay/configuration/ios/v4