My samsung galaxy 5s started sending me the same message yesterday, saying it came from myself! At first i thought i was maxed out on text so i deleted quite a few but nothing new came through. I sent a message to myself from my other phone number and it came through fine so i deleted the "insufficient..." message. Until it came across again today (twice 2 mins apart) so i stopped at my local verizon store they had no idea so no issues with my account gave me the 800 number to call, but they have no idea either. They fear it may be a phishing scam so advised me just to delete if anymore come across while they investigate! You mentione you recently "blocked" a number, so did i! Maybe there is some connection?
I have the galaxy s6. I disgruntlely had to message the person to see if they could delete the message they had attempted to send and so far it seems to have stopped. I had quite literally received over 100 for two texts that weren't going through. Quite annoying.
I also just blocked a number and two hours later I received my first "Recipient has insufficient funds to receive message" message. That must be the cause of it because it's the only thing that we have in common. I have the Note 5 and never received this message until I blocked the number. The message usually comes thru on the times that the person I blocked normally text me. Maybe it's the phone trying to tell us that the blocked person is trying to text us.
I have been receiving the same text and just blocked a number as well so just to see if that was the reason, I downloaded texting app with a different phone number blocked the number and attempted to txt myself and I instantly received the message Recipient has insufficient funds to receive message.