The universe is telling you to stop being so hard on yourself when it comes to money and other material things.
The go-getters number is 644. Don't give up, even if it seems like you've been working very hard and nothing seems to be happening as a result.
Maintain your constant work ethic as you have up until now and trust that the angels will assist you.
If you desire it, you might soon be offered a raise, a promotion, or a job.
Regarding financial matters, another interpretation of the angel number 644 is that you are overly preoccupied with earning money and neglecting other aspects of your life.
You might also be earning your money illegally, have concerns about what your superior is doing, etc. You need to take action to set things straight in this situation.