if so和if not的区别

if so和if not的区别
这样一个句子：
You are not happy.If not,I can make you happy.
这里的if not表示if you are not happy,
当句子改为
You have some problems and you are not happy.If I can make you happy.
这里的if后面应该填so还是not?如果是so,不就变成了If you are happy,这样不就和后面的话矛盾了吗?
如果填not,就变成了If you don't have problems
这也与原句有矛盾?应该怎么办?