Binance want us to have more on the futures account for some pair then for the other.
You can try reduce your BO and SO or run less deals on same account or add more funds to the account.
As stated in this Binance article:
The maximum amount of leverage available for users depends on the notional value of their position.
https://binance.zendesk.com/hc/en-us/articles/360033162192-Leverage-and-Margin
