Bad batch

Hi, I wonder if you ever experienced problem with some bad batch of rum. It happens to me twice, that i bought a bottle of rum which a liked, but new bottle tastes differently than the previous one. First case was Pyrat XO. I have finished one bottle which I quite liked for its orange aroma and flavour so I become new bottle as a gift. But there was nothing like aroma only bad smell of alcohol. taste was notably more harsch. But still it was drinkable with reservations. Second case was even worse, according to many references and reviews I decided to try Aniversario reserva exclusiva, but strong smell cleanser and strong alcohol taste absolutely did not meet the references and it was worst bottle of rum I have ever bought, but I dont believe that this is its usual taste. So did something like that happened to some of you? Is it common? Can I do something with it, return bottle or something.