It would depend somewhat on if you can conclude there is absolutely no one (or not enough people) who are willing and able to pay money for what you have made. And also if you need to earn money again soon to live off.

Is there any avenues to find out from the market why they are not buying. I'd suggest calling everyone who was on the trial and interviewing them. Come up with a set of questions that is to discover why they didn't buy. Maybe they loved it but couldn't get approval? Maybe they were just trying out because they liked you or are friends but the product doesn't really solve a problem for them?

I'd give it a deadline (3 months). Spent that time trying to proving beyond any doubt the product is a failure so you can finally scrap it. If it isn't a dud then use the information to form a plan to sell your solution to people. Also keep an eye out for a pivot.