A tip from me.
Pretend that you know your purpose. How would you feel? What would you be doing? What would your life be like? What might you be experiencing?
When you do a discovering your purpose exercise go into it with the expectation of finding it. All too often we start with the mindset, 'I don't know what my purpose is and I don't know how I will find it.' Instead imagine you are at a door and opening it and behind that door is your ideal life. What is it?
Whatever you get therein lies a purpose. Don't think you've only got one purpose in life, there are many ways to get to a destination so what you might find is an essence.
Be playful too. If you're purpose is quickly met then there will be a new one on the horizon. So go with what you find because it might just be opening the door to the ultimate purpose.
One way to find your purpose is pretend you already know it.