Secure Boot keeps re-enabling

[Leo412]

I have a Lenovo Ideapad S145 and I am trying to boot from USB but every time I disable secure boot and try to boot from usb, it tells me I need to change my secure boot settings. - Then I go back to the BIOS setup utility only to find it has been enabled again.

I have tried everything I could find on the net like adding admin passwords etc. but nothing seems to work. It just re-enabling secure boot after I disable UEFI Secure Boot it and save.

Please help

 

[Throttle1837]

1) Enter bios settings
2) Change secure boot to 'Disable'
3) Save and exit bios
4) Wait for the computer to restart. DON'T PRESS ANY KEYS IN THE MEANWHILE.
5) The screen fills with: boot options have changed. It says you have to enter some numbers and press enter to confirm.
6) Enter the numbers on the screen and press enter.

Your settings has changed after confirming.