There is a fundamental problem here. And you won't fix it with adwords.
It comes from the 20th century methodology of focusing on the product first. In the industrial age, product was the hard thing to do, especially at scale. Customers were easy.
In the digital world, product is easy, customers are hard.
But there is a spiral. If something fulfils a real need and is well presented, attractively priced and with obvious value, then it gains traction.
This traction becomes a buzz - people tell others, journalists write about it (and beat a path to your door for stories), stores want to stock it (if it is that type of product). The buzz escalates - as more people hear, they tell more people, who tell more people etc. Done well you become the byword for the niche you serve - people talk about their Slack account as almost generic for collaboration, for example, dropbox for their storage etc.
You can help this along the way. Good design, which attracts and presents key hooks in a compelling way. A hype programme which influences the influencers, feeds the journalists and positions you as the default, the growing, the must-have. And an availability programme which makes it easy to sign up, to get onboard, to build it into your daily routines and to share.
But we are afflicted by a sixties sales mindset. Then the key to more sales was to knock on more doors, with the same pitch. Or to advertise, undifferentiatedly to everybody - "hell who cares how many wrong people we waste the time of, as long as we get somebody buying the product".
This push mentality means that rather than fix what is wrong with our product market fit, we'd rather spend fortunes annoying people on Google, sending email after email, or writing content and more content.
But this has a downward spiral. Our cost of sale rockets. And gently people tune out - you are just noise to them. Eventually it all grinds to a messy halt and a forced pivot.
So don't follow the downward spiral - follow the upward one. Build something so compelling people want to talk about it. And by something, I don';t mean a product, but an offering - something people want to use, to subscribe to, to own and will tell their friends about.
There is a key to that.
Get rid of the fixed product and customer mindset.
Stop thinking of people as users - just numbers to validate your product.
Think of yourselves as enablers, helping them to solve a problem, find an opportunity, move their lives forward. Once you see things through their eyes, you'll see why they want it, how many do and how they spread the word.