How do I prevent code being read from the SAMD21 M0 Xiao?

Hi everyone,

I have been looking all over for a solution to this online but it is confusing me. The following two links both suggest they should enable the read protect fuses on the SAMD21 but when I have tried it on my xiao, I can still press the boot pin twice and copy the uf2 file from the xiao onto my hard drive.

https://industruino.com/blog/our-news-1/post/security-bit-47

What is the correct way to set the security bits so that the code cannot be read? I am happy to use another bootloader if needed

Thanks in advance

Regards,
Al.