I've recently got the Asus ROG 3 and I've had to manually enter APN details to get data access. Unfortunately, the 4G speeds I'm getting in Manchester are really low. It is averaging about 5Mbps download. In the same location with the Pixel 4 I was getting 50 to 60 Mbps. The Asus ROG 3 supports all the Virgin Mobile bands so that is not an issue.
I thought maybe I have the wrong APN settings. Could someone tell me what APN details I should have.