Buying Multiple Snowflakes With Old Snowflakes Bugged

I am converting my old flakes to new. The first three (tiny, delicate, and glittering) let me put in my full balance for a one-shot conversion. Well over 1K flakes in each case. But with unique, pristine, and flawless, it just changes the number in the "cost" column to what I put in. Sample image at https://cdn.discordapp.com/attachments/375715891280609285/390212201086058496/SnowflakeExchange.JPG

I am trying to type 1946 in the buy number box, but it stops at 19. Pressing "Buy" does not reduce my 1946 flakes, it just changes the vendor listing as shown. The same behavior is occurring on the other two. I am able to do it in smaller batches -- I think I got up to 50 at a time on the pristine ones.

It is slowly letting me convert, so it's not game-stopping, but it's definitely wonky and making it tedious to do the swap.

EDIT: Well hmm. Looks like it's because my bags filled up with snowflakes so the vendor wouldn't sell me more 'til I had room. Which is a separate problem -- all my flakes fit in my bank before, but the exchanged ones are an inventory nightmare (thanks be for the Snow Diamond there).

You can just right-click to "convert all" instead.

NOW you tell me :)