BBM's chat problem

Hi. I use blackberry Z10 on the most fresh OS. I have used BBM for chatting and for calls a month or two, but one day as usual I wanted to use the chat and it stopped sending. It shows red cross mark, and I am not able to send messages via BBM, but can make calls. Also the BBM is on the last update and I looked even through all settings. How to fix this?

Posted via CB10

have you rebooted your phone lately?

Sorry for asking, rebooting is restarting the phone? Or it can be done by connecting to the computer?

Posted via CB10