DaSchief said:

My Royal Cannon which was at level 6 yesterday is now level 1. I am having to upgrade all over again.

Is there a question here? 

First, the obvious: are you sure you didn't get hit (raided, blocked, Fireshipped)?

Second, if you didn't, please, either provide your ID string (you can get it by clicking on it in the bottom left of the Help window) or specify which platform (Plarium (app included) or FB), server (The Pirate Bay/The Golden Coast/Sirens' Strait), and coordinates you're playing at.