Epson TM-C3500 Series Technical Reference Manual page 146

Printing barcode and 2D symbol
Sets specified number of point, language of the replaced True Type font by barcode and 2D
symbol font to the print data.
 The number of point for barcode and 2D symbol is specified, check it from [Barcode and
 The replaced True Type font can be used only for specifying barcode and 2D symbol,
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2D Symbol] on [Driver Utilities]. The barcode and 2D symbol can not be printed if a
value other than those specified is set.
therefore, if the character other than specified is used can not be printed. Make sure to
use True Type font that is not be used for other printing.