What is wrong with my eeprom?
You say it's a write protection pin, implying that asserting it prevents writes.  Note that the pin name is written with a bar over it in the schematic.  That means negative logic.  Tying it low therefore asserts its function.  If it is truly a write protect pin, then you are preventing writes by tying it low.

Since you didn't provide a link to the datasheet, I'll leave it to you to check what the function and polarity of the pin really are.