Need to import Booking.com data to wordpress theme.

We need wp import all plugin expert to import data of 2,000,000 hotels and their Rooms from API by using wp import all plugin. We already had Plugin, we already have all Data API's and formatted Templates for that. The only thing is need to import all data within 10 days. We are getting slow importing [login to view URL] you need to optimise wordpress DB to speed up importing process. So if anyone had experience to import data without any issue by given [login to view URL] bid.