I bought a Sig Sauer P229 9mm in 2009 from California. I purchased a few 15 round magazines recently (I live in FL now) and it says Sig Sauer P229-1 on the side. I tried to use them today and they don't slide in. They seem to get hung up. I guess I have been using them in my M-11 and never used them in my P229. I took them in and was told they are newer magazines and don't fit in the older model P229's. I'm really disappointed. Do you have any advice?