Welcome to you.
I agree with Elli that this nipping is normal puppy behavior and as GSD's are herding dogs they tend to move us (their stock) by nipping sometimes. This is correctable. Since you have found the soft muzzle is affective I would say good, please just do not over use it.
URO3,UCD Aleshanee Windridge "Kayos" CD,TDX,RE,CGC,HIC,TC
PTE,AG2,AN,URO3,UCD Xtra!Xtra! V TeMar "Havoc" CDX,GN,RE,CGC,HIC,TC,BH
UACH,URO1 Tidmores Rising Star Lydia "Mayhem" CD,BN,AX,OAJ,NF,RE,HT,TC,CGC,
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