134.2k RFID Incorrect Readout

Hi, Wondering if anyone could help me.

Making a RFID reader to read Livestock tags and display on a screen.

Using this RFID reader - Wl-134 134.2k AGV RFID Animal Tag Reader Module TTL Fdx-b Iso11784 Long Distance for sale online | eBay

Now currently running tests, using an animal tag Number - ( 704571 00432 ) (Number on the tag)

Once scanned, This should Display on the Screen as - ( 828 704571 00432 ) Tested with another reader and it works.

But currently its displaying - ( 248575648505755448496551514848494849484848481231323 )

Wondering if anyone knew what the problem was? or any advice?

Thankyou