Siri not sending texts

When dictated, Siri is not sending texts any more. It used to work like a charm but not any more. I ask Siri to send a text to a contact, it listens and asks what I want to say. So far so good. I dictate the message but it doesn’t register, as it keeps asking until ut tells me it didn’t hear anything and quits. It’s not the accent since I’ve done this for years without a hitch and it responds to everything else. Only started happening since about last 2 months. Maybe a software update messed something up? How do I fix it?