You are using two different hierarchies of the same dimension [Dim Course] in the tuple which is not allowed.
You will have to change your query, something like this should work:
select {[Measures].[Dim Course Count],[Measures].[Dim Semester Count]} on 0,
{([Dim Course].[Course Code].[Course Code], [Dim Semester].[Academic Year].[Academic Year]) } on 1
from [CCSE-DM]
where [Dim Course].[Level1].[Level1]
This resolved the error. Thanks for the help.
@T.Com glad it helped. If the problem is solved you can mark the answer as accepted. Thanks.