flat file loading error

Hi,

i am new to sap bi and facing problems in master data extraction through flat file. my sample data is

mid mname mplant

m001 shoes uk

m002 trainers usa

Data is correctly got loaded into the PSA. But DTP is getting failed and upon diagonis it says *Data record 1 & with the key 'm001 &' is invalid in value 'uk &' of the attribute/characteristics MPLANT &.

Thanks in advance

krishn