Hello,
This can happen sometimes when it gets very hot in the delivery trucks and causes pressure to build in the bottle causing it to "pop" when opening for the first time. If you are ever concerned about a bottle seal. we will happily replace it for you.
I hope this answers your question. Feel free to reach out directly to us if you have any more questions.
Thank you for contacting Lunakai and have a nice day.
Warmly,
Bella D.
Lunakai Customer Service Manager
Nashville, TN, USA