qrz.com isn´t an electronic QSL service (only another online log). So they don´t use any message field. What they are using is only the comment field but this is not the message which you have stored in QSL & Labels. This one works on eQSL.cc and for labels you print wit a label printer.
73´s .. Juergen ... ALT-512 SDR (10W) , 50 m random wire at SG-211 autotuner, 2 x Xiegu G90 (20W HF TRX) one as portable Radio. Also TS-790E (40 W) for VHF/UHF with X-50 vertical and Duoband 4-Element LPDA.