Hey,
I ran into the same issue when I was using DB Toolkit for the first time.
If you INITIALLY create the fields wrong (e.g. create a text field as an integer) DB Toolkit cannot fix it for you, even if you change it and save again.
To correct this you need to have database access – MySQL, phpMyAdmin, something like that. Then you can open the database and correct the field types.
I hope that helps!!
