Why isint my Lumia 635 update to Win 10 Mobile not working?

[WINDOW LOVIN]

I have followed every step. Downloaded windows insider, signed up, updated to denim . And went back to the insider app and clicked FAST...rebooted and bam. Nothing happened, so I looked for updates and just got an error and phone wont back up and everytime I try to click and FAST to Update. It just reboots with no changes! Why??

 

[trueaction10]

Once change slow and reboot. And then fast and reboot.

 

[WINDOW LOVIN]

ive tried both repeadly...still the same. itr just wont allow windows 10 on mine but have all the requirements.