Amazon is building up a huge in-house delivery network that now moves the majority of its packages.

Rakuten Intelligence said Amazon’s percentage of late deliveries has doubled from 2017 to 2019 as the retailer increasingly turns to its own delivery network.

But Amazon Beg to differ and told Business Insider that the numbers reported are not accurate.

“Rakuten Intelligence continues to report inaccurate numbers and the data they are sharing is wrong,” the spokesperson said in a statement.

Either way, Amazon is working to improve their own delivery service that one day may compete with the traditional ones