My dataset as like below.

[![enter image description here](https://i.stack.imgur.com/fRPoM.png)](https://i.stack.imgur.com/fRPoM.png)

Subject column refers to Email SUbject and Problem description and Problem details column refers to Email body. 

Based on both subject and emaail body keywords, i need to classify to which Queue it should belong to. 

Previous queue column consists of 25+ different categories. 

My dataframe shape is of (60697, 4).

Please advise on the approach i need to follow to classify. Which ML models i need to use to train the data and test the data.

I know a bit to use natural language tokenization concepts. 

Classification is more like gmail inbox classification: Primary, Social and Promotions. However, here I have to categorize into 25+.