hard to soft buds

me and my brother grew the same seeds and both were looking good nice hard buds then last 2 weeks both went fluffy. why?

Do you have pictures?

Wild guess no pics
Harvested too early
Sorry

no pic but the buds were nice and frosty and hard had 2 weeks 2 go then went fluffy and my brothers just did the same on him. the seeds were from last years crop ,my plants got pollan from someware . was thinking maybe its the seeds