Exactly this.
Same situation here. Happened again just this week trying to buy more stuff. Called a couple times Monday. A couple more today. No answer, so not going to beg them to take my money. The sale goes to another business that answers their phone.
It's been the same situation over the years. Surprisingly no change. I only keep trying because for some items, they're the only place to get them or best price.
It's not their first import though. You'd think by now they'd be able to predict when it gets busy and plan accordingly to have adequate manpower instead of letting the phone ring.