The vocal sounds a bit dull and it clashes with a lot of the low mid frequency content in the instruments. I recommend cutting some of the low mid frequencies and boosting the highs from the vocal to make it sound more exciting and also sit in the mix better. Also a very short room ambience reverb would help it sound more natural (the point is not to sound like it has reverb in it, the point is to sound like any sound you hear IRL because everything always has those room reflections).
There are also a bunch of problems with the instruments themselves. The bass instrument (which sounds like a synth piano) is off center, which makes the whole thing sound very unsettling on headphones, but at the same time, the overall mix doesn't have all that much stereo width in general. Assuming that you're dealing with an instrumental track and you don't get to have control over each individual instrument, the best way to mitigate this is to use a multiband stereo imager and merge the lowest band as much as you can without making the bass disappear, and add a bit of stereo separation on the other bands.
A bit of multiband compression on the master would also help with all of the issues. You don't want to squash the dynamics too much in this song, but a little bit won't hurt.