Blinking when playing animation in game

dk111

Hello,
we're working on Phaser 3 (Spine Runtime 3.8.99).
Recently there's an issue when playing two animations continuously.
Although I'm not sure if it's related to sequential animation.

00:06 - You can see an image blinking before the animation starts.

Our animator says

there's nothing wrong with the original animation https://slack-files.com/T17642NPR-F03QR7ZBPJL-2dc53640f9
when she set something on Spine's setup screen, it shows up in game as well.

Is there anything you can come up with? We can't find how to deal with this.
Thank you in advance!