Thank you, guys, for feedback. Again, I must start my first message with apologies. I've been testing save system and I really thought everything was okay with that. I do understand all the negative toward the game, because if I were you I would have said the same: "grind->grind->bug->wtf? And no way to properly save my progress?!"
It was a deliberate choice to work with Unity for it has Fungus plugin where you can build the game without any scripting. RenPy is the easiest way for developers who actually understand something about coding (real programmers will spit on my face, but it's coding, primitive, but still coding there).
I've been thinking about possible solutions of what should I do now and I've come up with this:
1. Switch to RenPy. The problem is that I'd have to learn this soft so it'd take time, a lot of time which I don't have. I gave everything to my game and unity, so taking extra time is of no option for me. Unless someone will help me with working with RenPy. Not just giving some tips how to do this and how to do that, but doing the whole work with it. I don't dare ask someone to do this work, simply I just don't have anything to pay for this hard work and I think there are hardly anyone who'd do it only because he/she is enthusiastic.
2. Reduce grind elements. So this is the most rational solution. Every kind of repetitive stuff will be reduced. For example, you need to buy a dress (100$ is 75 now), you work in Storehouse (mrn, afternoon, evn - 25$) and you'll buy it in just a day and so on. Just reimagine the game from ADV to story-driven game. That barely can compensate the lack of save system, but still it is something. I found an example of save system with slots, but this time I won't promise anything.
No matter what, I'll be working on this game and I'll finish it.