Hi @marslan,
Did you have OpenZeppelin Contracts 2.5 installed? npm install @openzeppelin/contracts@2.5? I am wondering if this caused the issue.
Your contract (Can't verify ERC20 contract importing OpenZeppelin) doesn’t have any constructor parameters if you verify manually on Etherscan.
I recommend the following method: Verify smart contract inheriting from OpenZeppelin Contracts
If you run into issues, let me know the address and I can try to help verify.
As an aside, ERC20Detailed was rolled into ERC20 in OpenZeppelin Contracts 3.x. You may want to look at using OpenZeppelin Contracts 3.x.