Musescore 4 and sfz

I use sfz for bell ringing scores (usually of three staffs). In Musescore 4 I use sforzando vst plugin. I have found that from time to time score could not be played because sfz not set for all staffs (sforzando is empty) and I need to set sfz again.
Also mixer shows me two sforzandos despite the fact that there is only one in the Plugins (Vst) folder
Any ideas how to solve identified problem?