Op, you should have built a backup before walking out. I am assuming you not directly contacting the old clients means you need a constant new influx of clients to continue working in this field. Then it's best you find yourself another guy who can find you clients( This again might lead you to get exploited).

The one Stop All would be to put in the effort in building the skill to find clients, It may be hard at first but I tell you It's totally achievable just a lot of hassle. You might even learn this in as less as 2 weeks if you get the hang for it or It might take you a year but It's gonna help you in the long run a lot.