Oh no, that's not fun, but we have an easy solution! If you add fresh lemon juice to the bottle, and shake it around so it covers the whole inside that should help. Be sure to thoroughly rinse the bottle with warm (not too hot!) soapy water and rinse. Give it a sniff. Is it better? Great!
Sparkle Pro-Tip: Avoid placing bottles face down on a counter-top for prolonged periods of time as this can lead to trapped moisture.