what should I do to bring back motivation in myself. so I can get excited about my job again?
Firstly you have to identify wat really the problem is or are, and try to deal with the root of the problem.
Identifying the problem has to do with first knowing the things that got you excited and why they stopped.
Try to always check your stress level and maintain healthy diets as well as checking your mental state, just try as much as possible to identify what really the problem is and the changes in your environment both at work and at home, and also does this problem occur for the both works ?
If yes, then is a state of health and not about the work.
But on the other hand, most time our works get boring, because our desires out grow our salaries and earnings and we want more, just as human desires never seize and we desire for more when we achieve one.