Can't add new words to Dictionary.

[Kamal GK]

Hello All,
I have Xiaomi Redmi 2. I am using Google Keyboard. When i bought it i can add the new words to the dictionary by pressing the word on top of the keyboard and 'Touch to Save it' Button. But the last few days i can't add it.. I don't know is the keyboard was updated automatically or not... How can i solve this...

Thanks..