How to regain old groups on new device

Hi,

I am new to this forum and have a query on WhatsApp. Hope someone will answer it.

How can I regain the various WhatsApp groups in my new phone? My old mobile had suddenly stopped working. When I installed WhatsApp in my new device, I am neither getting my old groups or chats back though I am using the same SIM. (I remember WhatsApp sync chat data every day in my old phone). Presently I am on Android 8.0.

Any pointers on the matter will be thankfully acknowledged.

Thanks and Regards,

Arvind Gupta.