Vanity Fair Womens Full Coverage Bra 40C

I have had four of these bras and are my everyday bra. I wear a full coverage 34DD, and this bra fits pretty well, although a bit too large in the top of the cup (I need a contour bra). There is no spill over on the sides or top of the cup. The band size is accurate. I am not easy to fit. I need both full coverage and a contour cup. It's lightly lined for no show through. However, the strap of the bra I just bought in March (6 months later) started coming undone without warning. The rest of the bra is still in good shape, but is unwearable due to the strap issue, therefore a 3 star rating, as the bra doesn't seem to last. I've thought about contacting Vanity Fair. Update: I did contact VF, and they replaced the bra, no problem. Good company to do business with. However, I don't know if it's me, but I've worn these bras for a loooong time, and now the 34DD is too large in the upper part of the cup, and tried the "sister size" 36D, and the both the cup size and band are too large. The 34D came CLOSE to fitting, but was a bit too small in the cup where there was a bit of "spillover". Sometimes it's just the lot of bras--some fit smaller, some larger, just like any mass-produced item. I just tried a 34D sale bra in Wacoal recently, which seemed to offer the best fit overall, with both good fit in the cup and the band.