Fast and reliable transport protocol for streaming text

Hello.
I am looking for a fast and reliable protocol for streaming big amount of small text data in real time (text strings might be between 20 and maybe 500 bytes long).
I do not care about order and when they arrive, i care just to get them to my server (100% delivery). I will have like almost 100 endpoints sending to one big server, so it will have heavy traffic.
I don't look for TCP as it is not connection-less and it might be heavy for the network, has large header.
I was thinking about using UDP but I saw that I loose some packets, sometimes even 1%+, which is not acceptable. I already did some testing.
I am also implemented KCP but i don't know if this is the right solution. I am still doing tests.
The implementation has to be compatible with C and Node.JS as i will run my app in different environments.
What do you recommend?
Thank you.