I checked your product and I think it comes very handy. But maybe I would try to get the customers onboard differently than the life time acces. Can they try your product? Or would they need to pay $99 upfront without real experience of the product?
I would let them try the product for free (as you build a feedback tool, I would ask them for feedback in exchange for free trial) and improve the product with the customer feedback! So you actually get value back.
And I would consider to set a different pricing strategy or at least experiment with it!
You can find your first customer anywhere the market is open to you
Start posting on groups and communities
Self Promote your product on LinkedIn, Twitter
Use hashtags while posting on social media platforms
Create a post on indie hackers
Run Ads