Board Thread:Questions and Answers/@comment-33004715-20171016155439/@comment-88.115.164.91-20171016160514

It seems to be telling you that you've bought too much quartz for this month. You appear to have set your age as 15 and thus have a limit of 5000 yen in purchases per month and have now spent 4920 yen.

I assume this happens when you try to buy more quartz.