I see two problems:
1.
You can't modify your database with ExecuteReader; that method only reads something from the database, it does never write anything to it. Use ExecuteNonQuery for inserts, updates, deletes...
2.
A lot of words (
list) are reserved in SQL and "Date" is one of them. Two solutions: (a) avoid using them as field names, that is the easiest way; (b) escape them in your SQL statement; the exact way to do that depends on the database being used, candidates are brackets as in [Date] and double quotes, which is somewhat harder to get right inside a string!
:)