Is there an issue using web SMS and Hangouts?

I am able to see/read my messages, but when I try to compose a new message and send it nothing happens. It appears to be sent in the web interface, but nothing is on my phone. I am on Android 4.4.2 and also have Hangouts as my default SMS app. Could this be an issue with the new "default" sms changes in Android or is there a setting I should be aware of.
Thanks.