SIO2SD - cant format

interesting bug?
-today i trying copy 5'25 to sio2sd.. 5'25 - D2, sio2sd - D1.. first copy d2, then format d1.. but system freeze..
then i try boot DOS 2.5 as normal and before and try format (I) ATR file.. dont work, freeze (cant stop with BREAK - error 128)

i trying save something to sio2sd - work fine.. only formating dont work.. hmm
writing DOS files (H) works fine