If Highlight shows that you're "not on whitelist", but you follow our criteria, it's an error on Highlight side. 

They can't process so interface doesn't allow anyone. I'm afraid you have to click refresh. 

Persistence is key.

Building /onchaincoin | 2D onchain woman | BD at /morpheus | Building an infra for IDOs to be backed by social capital at /frensly

Finally worked for me on Coinbase wallet. I had to open the mint link directly in my wallet browser for it to work after refreshing a few times 🙏🏼