I am using the iPhone 7 and I recently purchased it. I used to prefer the 2g, 3g, and 4g manually but I tried once to choose the LTE technology manually. So when I tried to lock Digi WR21 to band 20 on LTE manually, it shows an error. I also checked <a href="https://iphonesupport.net/iphone-customer-support-number/"> Apple iPhone Support</a> and tried to take some help. So is there any way do it manually anyhow??