Problem with "create multiple" command.

Hello,
I am using the Navision 2016 web services in order to insert record arrays on databases. I am using Visual Studio.net 2010.
Using the command "create" the program works correctly, but with the same data, using the command "create multiple" just the "string" type fields are handled correctly, while the others are ignored without showing any errors.
Help me please, I cannot use the "create" command because I need to handle a lot of data.
Thank you.