Error when simulating a load from a flat file

I encounter the following message (below) when I simulate a load from a flat file. All the key figures are defined as:

DEC - Counter or amount field with comma and sign

This is how they have been defined in a previous BW system in which the file loaded without any problem. How can I resolve? Thanks

Diagnosis

The value '1,000 ' from field /BIC/KFMI_QTY cannot be converted into the

DDIC data type DEC of the InfoObject in data record 1 . The field

content could not be transferred into the communication structure

format.

System response

The data to be loaded has a data error or field /BIC/KFMI_QTY of the

transfer structure is mapped to an unsuitable InfoObject.

The conversion of the transfer structure into the communication

structure was cancelled. The processing of data records with errors was

continued with respect to the settings in the error handling of the

InfoPackage (Tab Page: Update Parameters).

Procedure

Check the data conformity of your data source in the source system.

On the 'InfoObject - Field Assignment' tab page in the transfer rules,

check the InfoObject-field assignment of transfer structure field

/BIC/KFMI_QTY .

If the data was temporarily saved in the PSA, you can also check the

received data for consistency in the PSA. If the data is available and

is correct in the source system and in the PSA, you have the option of

activating the debugging in the transfer rules by using the update

simulation on the tab page Detail in the monitor. By doing this, you

can execute an error analysis in the transfer rules. For this you need

ABAP knowldege.