This is rough but its kinda to be expected of someone relatively new to game dev.
I never really liked more frustrating tedious games like Flappy Bird, so no surprise I wasn't a big fan of this either. But I will say it did at least add a twist by having a grapple so there was a bit more challenge and tact behind staying afloat. At the same time, it felt really unforgiving and I enver made it past a score of 3. I'm assuming since its based on flappy bird that was intentional, but in any case not for me.
One piece of advice I've heard from 2D platforming devs is to not make damage collision pixel perfect on the player character, so if you just barely brush the wall at one pixel you don't die. For this game maybe that's something to try out, maybe not.
Also, there doesn't seem to be a devlog for your game?