The table have issue. select is empty but can't insert more data

Hi all,

I have issue when insert new data to my table. The error return is DUP RIMARY KEY. But when we select this table. the result show no data. after that, I select info of this table information_schema. the result returns the number of rows in this table other than zero. (select * from information_schema.`TABLES` where .... ). I only can insert when I drop and create again this table. Please help to explain the root cause and how to repeat this issue.

Thanks advance!