.rpc and PGRST202

Hi, I have a few .rpc functions, and most of them are working fine. I wrote one today to use in a dynamic route and am getting PGRST202 error, although it does sometimes work. I tried scheme cache reloading. The .rpc is quite simple and just takes a uuid from the url and then uses this to fetch data from a few tables to display on the page. Has anyone else has intermittent issues with PGRST202?