Error Mining Altcoin node, coinbase timestamp is too early

[Goldbach]

Junk Please

[dukemc]

I've tried looking through bitcointalk but to not much help.

I recently have been attempting to clone an altcoin, and i have created a genesis block a few days ago.

However, when I now try to mine for more blocks, I run into this error:
ERROR: CheckBlock() : coinbase timestamp is too early

Does anyone know why this may be caused?

Maybe its a firewall problem to connection to your masternode check your internal firewall config.