It is really a big problem if you forget the passcode of the iPhone. I had once been there and was locked out after 6 attempts with wrong passcode. Therefore I could not backup my iPhone. Luckily I found a solution. So how to backup iPhone without passcode? Actually you can then reset the passcode, but it is also possible to backup the device first without typing the passcode. In addition, you can access your iTunes or iCloud backup without passcode, all you need is an iOS data recovery program.
OnePlus 5T review: Hands-on