God didn’t lie. He fulfilled that covenant in Jesus. Hence, Old Covenant and New Covenant. The Jews reject the Son and therefore reject the Father. They must accept Christ to be saved.
So when God said”Gen_9:9 And I, behold, I establish my covenant with you, and with your seed after you; “, He was lying.
I’m just making sure you don’t believe your god can keep a promise.
Mine can.