Where do i begin?

[mohamedthecomet]

Back in January of this year, i contacted a seller to do an animated video for a cheesy rap song i made.  I was quoted 21 days for a storyboard (milestone 1), 21 days for an update (milestone 2) and 18 days for milestone 3 (completion).  Instead of a 60 day completion, it has been 230 days (and counting) and it is still not even close to finished.  Unfortunately i have paid for the storyboard, as well as an update showing partial progression from the animatic.  Just to give you an example of the timeline, i was given only 25% of the the storyboard on the deadline for it. 

The equivalent of the 2 payments i've made so far was roughly 55% of the entire agreed upon price.  Last message i got from him was over 2 weeks ago. I keep getting excuses like "my internet is down" .. or "i have a new job and am busy" .. or "i have another project i'm working on".  Same excuses over and over (mostly internet down) and it is really testing my patience.  This is my first time trying Fiverr and this experience has been horrendous.  I would like to see this thing through, considering he already has most of the payment and i'm kind of stuck dealing with his reasons of not meeting deadlines. He keeps extending it, and i keep allowing it.  

Any thoughts on what my options are?