I had to re-root my phone. And I noticed there were some issues with OPs thread so here are the steps I took in order to get a successful root on the 10.0.7.
1. Unlock your phone.
2. Download twrp-3.3.1-5-hotdog-unified-mauronofrio.img from here:
https://xdaforums.com/7t-pro-mclaren/how-to/how-to-guide-root-oneplus-7t-pro-t4021325 (step 5)
3. Put your phone in fastboot-mode and type: fastboot boot twrp-3.3.1-5-hotdog-unified-mauronofrio.img
4. Go inside TWRP (Swipe right)
5. Run these commands while your phone showing TWRP recovery normally and connected to your pc.
adb shell dd if=/dev/block/bootdevice/by-name/boot_a of=/boot_a.img
adb pull /boot_a.img c:\android\
Note: You'll now get a boot_a.img on your pc at c:\android\boot_a.img
6. Download & install Magisk Manager on your phone
7. Copy the c:\android\boot_a.img over to your phone
8. Open the magisk manager app and click the "Advanced Settings" button, then check these:
> Prserve AVB 2.0/dm-verity
> Preserve force encryption"
Then select the top "Install" button -> Tap "Install" -> Tap: "Select and patch a file" and select the boot_a.img from earlier.
9. on your phone you'll see where the magisk creates a new patched boot image. Transfer this file over to your pc. You'll likely need to reconnect the cable in order to refresh folder data to locate the new file.
10. Put your phone in fastboot-mode
11. Run these commands:
fastboot --set-active=b
fastboot boot magisk_patched.img
12. Phone will now boot with no wifi working. That's normal. Open Magisk and tap top "Install"-button again. Now click Direct Install. Then Reboot.
Note: If for some reason Magisk hangs during step 12 above you'll need to restart from step 11 again. Dont rush it when you start Magisk. Leave the phone alone for a minute after booting up and you should succeed.
That's it. Worked for me.