Error when trying to insert dates into database

When I use the insert function to write multiple rows of data to a database, I receive an error.

I'm using the insert function like this:

insert(conn,tableName,colNames,data_table);

One of my columns is a date. I've tried inserting the data in various formats: 'YYYY-MM-DD' and 'YYYY-MM-DD HH:MM:SS'. For some reason I continue to get this error:

Error using database.ODBCConnection/insert (line 189)
ODBC Driver Error: Invalid string or buffer length

When I try to insert the data without the date column, the insert function works without error. When I write SQL to insert the data, including dates, with the exec function the format 'YYYY-MM-DD' is accepted:

exec(conn,sql_string);

It seems like the date column is what is causing the problem with the insert function, because it works when I eliminate that column. Are there any suggestions for fixing this error? Thanks.