iPad messages to android users fail

Up until today, messages from the iPad to android worked fine. All of a sudden we get “message failed”. Resending it doesn’t work. We have looked through all the help sites, and have done everything they suggest, but still getting message failed.

We tried a number of sample text messages and get the failed note. We even reset the network settings.

Update: Now I am really confused. My wife noticed that even though we get Message Failed and not delivered in the IPad., they did appear on the iPhone and evidently actually did go out. On the iPad, however, it still said failed and no delivered.