22 subscribers since the first post in March seems pretty typical for around here, in my opinion. Problem is, it's always been that way and never ever changed since independent novels started.
The only ways I know to get yourself some traction is to upload daily if possible, have an appealing cover, have a curious name, and be of a genre that's hot. I had a lot of books on Tapas at one point and the only time any of my work had a consistent time of growth was when I was able to update every 1-2 days for a month. It's frequency in the recently updated lists got clicks, and then those new views added to the algorithm, getting the book to hang out in the Trending list, which in turn helped it again.
The moment my real life didn't let me upload often, it died. Straight into the ground.