Checkboxes results are not copied on the Database

Hello to all and thanks for everything...
I have created this form
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http://a21-granada.org/red-gramas/index.php?option=com_chronoforms6&chronoform=votacion_1
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The results of the checkboxes fields are not copied onto the Database...
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Can somebody please give me some advice?
Tanks a lot in advance
José