Based on the error, you have a Java action "Send text", that doesn't actually do anything. You get that error in Mendix if you create a new Java action but don't ever add any code to it. Mendix leaves a stub in there that throws an exception saying "Java action not implemented."
Since you're using an app store module, either the module is missing some code, or it got deleted in your working copy somehow. If you haven't touched the Java code in the module at all, try deleting and re-downloading the module from the app store.