I'm not a technician myself but maybe I can still help.
In general, a good entry point for getting help would be the Haunted PS1 discord. There's a dedicated #hpsxrp channel with a valuable history of problem-solving. I did a quick search. It seems that some people have run into this exact issue.
One person was able to resolve this by checking whether git LFS is installed and installing it if this wasn't the case.
If that doesn't do the trick, check out the discord. The peeps there will gladly help where they can, I'm sure.