Khan,
Not to question your experience but this seems very odd compaired to my experiences. I have used their MGF along with IGF-1 Lr3 off and on for months and had never had any issues what so ever. Tried the PEG with great results. As a matter of fact, feeling of quality is why I stay with these guys (and service).
Is there a chance the top of the stopper got dirty/exposed or maybe your pin?