我的查询有问题吗？我错误地使用Inner Join吗？

I could use some assistance with my exam project, I have a problem with my SQL query for getting a list of volunteers(id) based on the guild(s)(id) they're in, it is a many to many relationship and have decided to use 'Inner Join' to tell my java program what id's are = to each other, but when I run it, it gives me the error 'com.microsoft.sqlserver.jdbc.SQLServerException: The index 1 is out of range.' Which supposedely means that the list I am trying to show is empty? Any immediate thoughts?I could use some assistance with my exam projec