Most times when I send a single text .. the person will receive it multiple times.. sometimes up to 6 I have restarted my phone, tried to switch to a next TXT app (textera). All without any success .. It does not happen all the time
I used to have google messages app but read somewhere that it can cause this problem so switched to textera.. normally the people i send to are not in same house .. but within 5 k .. I can try the RCS change