Tsql – Cannot resolve the collation conflict

I am getting the following error message.

Cannot resolve the collation conflict between "Latin1_General_CI_AI" and "SQL_Latin1_General_CP1_CI_AS" in the equal to operation.

I only get it when I place this code below in my WHERE clause.

WHERE Region IN (SELECT Token FROM dbo.getParmsFromString(@Region))

Now @Region contains all the values from my multi-select fields from SSRS.

Below is the code for the function that is used.

CREATE FUNCTION [dbo].[getParmsFromString]
    (@String VARCHAR(MAX))
RETURNS @Parms TABLE
(
    Token VARCHAR(MAX)
)
AS
BEGIN
    IF CHARINDEX(',', @String) != 0
    BEGIN
        ;WITH cte0(Token, List) AS
              (
                SELECT   SUBSTRING(@String, 1, CHARINDEX(',',@String,1) - 1)
                        ,SUBSTRING(@String,CHARINDEX(',',@String,1) + 1, LEN(@String)) + ','

                UNION ALL

                SELECT     SUBSTRING(List,1,ISNULL(CHARINDEX(',',List,1) - 1,1))
                        ,SUBSTRING(List,CHARINDEX(',',List,1) + 1, LEN(List))
                FROM cte0
                WHERE LEN(cte0.List) > 0
              )

            INSERT INTO @Parms (Token)
            SELECT Token
            FROM cte0
            OPTION (MAXRECURSION 0)
        RETURN;
    END

    ELSE
        INSERT INTO @Parms
            SELECT @String
        RETURN;
END