Spigot furniturelib not starting up

So me an my friend have been trying to get a furniture plugin to work on our server but it says Furniturelib won't start. I deleted the furniturelib_1_12 final and kept the one compatible with 1.14 and 1.13 but it still won't start. I'm using furniturelib 2.1.4 and it just doesn't start. I've tried the alpha versions too but that doesn't work. I will attach a txt file with part of the log that mentions a warning to do with furniturelib.