RFID User Data Mismatch

We have a plant using MDS 426 (ISO 15693) as RFID tag and different types of RFID reader/writes include RF340R and reader/writer from different vendor other than Siemens.

All RFID reader/writer support ISO 15693 ,however, when we using other RFID reader to read the MDS 426 written by RF340R. The read arrary is inverted per 8 bytes. for example:

RF340R wirte byte array 1;2;3;4;5;6;7;8;9;10;11;12;13;14;15;16 to the tag, the byte arrary read by other RFID reader is 8;7;6;5;4;3;2;1;16;15;14;13;12;11;10;9.

Same problem vice versa.

Is this because the Siemens RFID funiction block write the user data into tag with special sequence? or the problem is from other RFID reader / writer? 

Thanks!