Having this same issue. No idea what’s going on. I have tried everything to remedy it with no solution.
so far I’ve; - clean install of gta and then revert game version because of yesterdays update, clean install of lspdfr, removed all mods besides lspdfr (so not mods folder issue or .asi mod), I had also updated my graphics card driver earlier so I reverted that back to the version that was working previously., I also went through the game files and “took ownership” as well as gave full access permissions to all users, thinking the issue was the inability to access a file RPH needed.
but absolutely no luck. RPH just opens and about 3 secs pass and it closes. So odd and so so so frustrating