ParserError: Source "@openzeppelin/contracts/token/ERC20/ERC20.sol" not found:

[frangio]

If you're developing locally you need to install @openzeppelin/contracts using npm.

Developing smart contracts - OpenZeppelin Docs

If you're trying to verify the contract, please see our guide:

How to verify a contract on Etherscan/BscScan/PolygonScan

Make sure to read this post before asking a question about verification. If your issue is not addressed here, just leave a comment below. If you want to pay someone to do the verification for you, create a post in Developer Wanted. This guide applies to all Etherscan instances, including all of the following as well as their testnet explorers: etherscan.io (Ethereum) bscscan.com (Binance Smart Chain) polygonscan.com (Polygon) snowtrace.io (Avalanche) Recommendations Practice in testnet Be…