Wi-Fi problems. I can't get emails, text, whatsapp or connect to any sites whilst I am using Wi-Fi in my office?

Many companies block connections from private devices to help prevent those devices from introducing virus infections on to the company's systems.

They may block specific ports, or direct those ports specifically to their own servers. For example, they will not want company email going to a private device, so they may direct the email ports to their own servers. This won't be apparent to you as email servers you use when away from work will require your credentials to access the servers, which the company will not be using.

The same is probably true for whatsapp. Normal text does not use the Internet connection but is carried as a special data service over cellular networks, so the company's network will not be involved in text transfers.

Check your company's IT policy. They may not sanction the use of private devices on their networks, and in some cases attempting to use a private device on a company network can be grounds for dismissal.

They block emails,so on the job you would spend more time for your work.

Firstly are you the only one who has this problem?
Did you have this issue before?

If what i am assuming is correct then the problem is not your phone but office wifi.
Try to talk to the person who administers the wifi at your office.
Most likely they may have put restrictions in what can be accessed.