US NEXO interest option when?

Why can’t we get Nexo as interest? I dislike having to buy NEXO via uniswap or matcha because of gas fees, just to increase my tier level. I’m sitting at silver now, a few NEXO short of gold, and would rather withdraw other assets so I get bumped up to gold since I’m from the US and can’t get NEXO any other way. I don’t want to use the exchange on NEXO since the fees are also high.