@futuretrainee You have some solid gold in the responses, but I would ask a few caveats to many of them.
1) How scalable are you (I assume that it's just you)? Can you manage infrastructure and resolve bugs all while managing customer relationship and scaling the business?
2) How did you identify pricing and are you sure that the model is sound? Leaving money on the table is much less problematic than not covering your basic capital expenditures - less than ideal to leave money on the table, sure, but if your CapEx are covered, you're starting to eat away at operational expenditures, which is a healthy place to be right out of the gate.
2.1) Can you augment the pricing model to encourage longer commitments with upfront cash infusions?
3) Are you setup in such a way that potential users can find you organically? Do you have basic SEO?
4) How does organic traffic sign up? Is it a manual process on your end and, if so, does it need to be or can you remove that hurdle? Is it the type of product that you can give a free trial for?
Personally, and without knowing specifics of your situation, I would not quit my current job until the business is already scaling enough to be able to get further funding rounds or obtain a line of credit from a bank. I would probably seek high equity, low/no pay, part time (for now) partners to be "founders" who can help to drive your current needs. Likely, that's another engineer, largely because they can drive features and fixes while you focus on whatever fire is under your ass that day and partially because they can do things like monitor DataDog/Sematext to get ahead of any problems that might make you lose your current customer. In addition, a senior product engineer _should_ be able to sit in meetings with the customer and iron out requirements for new features and fixes to existing ones without you needing to explicitly be present.
From a marketing side, I would let things sail for a bit, honestly. Work closely with the client you have and make sure that you're continuing to meet expectations, ideally, exceeding them. At the same time, see if you can start conversations up with some of the old customers that left - not because you're trying to sell them anything, but because you have pivoted and are doing market research, hoping to get feedback from people who have seen the old product and the new. Never, and I mean _never_, mention signing them up or pricing or anything - these are just research convos until _they_ ask _you_ if it would be possible to have a trial license or whatever. Keep in mind that these are people who potentially feel like "you" burned them before, so there's a fragile enough relationship without you pressuring them to buy.
When you start to feel like it's the right time (it could be that you're seeing people in your software a meaningful amount or you've added enough features and smoothed enough rough edges that it doesn't feel like an MVP), see if any of your users would be willing to share their experience with their network. Word of mouth is incredibly valuable and you'll likely have a solid reach to your ICP without even knowing who they are and literally zero marketing spend.
Something that I've seen kill a number of businesses is premature scaling, which is ironic because scaling to slowly is also a pretty solid killer. How can you minimize spend (aka maximize runway) while keeping a sustainable growth rate?