Chromecast Compatibility with Kodi

Hi, new poster here so hope this is the right place for this. I have Chromecast to cast Kodi from my Samsung phone to my tv. I’ve added all the repositories etc. And when I try to open some of them (most of them) I get this message: “This google cast device cannot play the video because of missing codecs OR Video was deleted or it is not reachable anymore.” LocalCast cannot fix this! Transcode your videos with http://www.handbrake.fr. What do I do? I’ve got Kodi Kypton v.17 and its pretty frustrating to see it trying to stream and then get this message. Any help greatly appreciated. Thank you.