protoc failed: file contains proto3 optional fields, but --experimental_allow_proto3_optional was not set

Fixes available online suggested modifying the code in libraries that I did not have access to.

So how to fix this issue without modifying any code?

1. remove current protobuf compiler:
   

   sudo apt remove protobuf-compiler
   

2. install older version (protoc-27.3 worked for me):
   

   curl -LO https://github.com/protocolbuffers/protobuf/releases/download/v27.3/protoc-27.3-linux-x86_64.zip
   unzip protoc-27.3-linux-x86_64.zip -d /usr/local
   chmod +x /usr/local/bin/protoc