No there is nothing in the new law about refund of money. You must also consider this as an insurance you had until december 2018. However in your case you only could use the insurance in the period october 2018-december 31, 2018 (because it requires 1 year membership). So off course I can see that it feels wrong.
But you could try to contact your A-kasse and ask them, but as mentioned nothing in the law saying that A-kasser should pay any money back.