App crashes if go back to chatlist before last seen is loaded in chat window

[Assadbintahir]

Steps:

• Install latest version from play store
• Once the application is opened, go to contacts.
• Open a chat from contacts
• Press back button before the last seen loads
• Application crashes

[Assadbintahir]

[status] I have worked on it. It is currently in progress. It will be completed today.

[Assadbintahir]

I have fixed this issue.

Code will be part of the pull request.

[jekram]

Thanks