Zero response from support so I guess I'll move on and cannot recommend this particular pack as I'm unable to get anything but a single sprite. The premium pack seems unavailable.
This just happens with this asset pack in particular or with the other asset packs too (from my bundle)? the last thing i can recommend its look out your email, and there search the email from the support@itch.io and enter to the link they sent you from my asset pack.
Well watching how this is looking, i have to do it myself, contact to me via twitter (X) in dm, if you dont have a twitter account, send me an email to my email (ferdamenz89@gmail), to see in more deep this issue and solve this.