I believe motivation is your worst enemy. I know, people say you gotta be motivated. But, in my opinion, you gotta be disciplined... At the end of the day, you cannot stay motivated every single day, it's not human and almost impossible.
It's like going to the gym, yes, you are motivated at first but the reason you keep going is discipline, because some days you don't really wanna go and lift weights, but if you are disciplined enough to go through it, you know you'll keep doing it for weeks, months, and years.
Also, creativity can honestly go away... try to do fun things, go out, and maybe from seeing something you'll get an idea. From there, write it down and think of something to make it entertaining.
There is a lot of things you can do, but you gotta be disciplined to be able to stay consistent. It's not motivation, but willpower!