Lose somebody/something in the shuffle
Definition 1 of 1
Pro Tip 1/3Chaos Implication
This phrase often implies a busy or chaotic environment where something was missed. 
During the office relocation, I'm afraid we lost your application in the shuffle.
Pro Tip 2/3Not Deliberate
It suggests that missing something was unintentional, not done on purpose. 
With so many emails coming in, we didn't mean to lose your message in the shuffle.
Pro Tip 3/3Metaphorical Use
The phrase is metaphorical and does not literally refer to shuffling cards or items. 
With so many talented artists, it's easy for beginners to get lost in the shuffle.