Need help with basic crypto in Erlang/Elixir: Decryption Error: Failed to decrypt:

Thanks for the reply.

these were the steps META provided for key creation:

openssl genrsa -des3 -out private.pem 2048
openssl rsa -in private.pem -outform PEM -pubout -out public.pem
openssl pkcs8 -topk8 -inform PEM -outform PEM -nocrypt -in private.pem -out private_unencrypted.pem