Well, this might even be unnecessary,but…
I am a sanshin player, and as said before, it Is not a sanshin. Neither it Is a sanxian, since the skin isn’t snakeskin and the dou isn’t round. (Sanxian Is similar to a sanshin but with a longer neck)
That shamisen seems not genuine. There are many factors that can differ it from a real shamisen. (Kamigoma,itomaki) Indeed it Is using a sanshin doukake (tiiga ティーガー)
So, maybe someone tried to make a shamisen with almost no knowledge and decided to sell them.
I’ve seen many people buy it and post their doubts in the forum.
Personally I don’t recommend it, but since it’s fairly cheap it can be a good starter shamisen.
If you wanna keep it, do what Joe said.