I swore on the Quran while lying and I'm very regretful of my sin, very. I can not fast 3 days or feed 10 people. Or pay the fee of committing this sin (reasons).
I made tawbah and prayed and made more tawbah. Am I still forgiven?
according to islamweb.net , it's a debt that you owe until you are capable. Also , you can appoint someone to feed on your behalf
I have faced the same issue before. You are forgiven insha allah swt. swearing on the book of allah for avoiding bigger problems such as ruining a marriage, ruining relationships between people that might lead to fights and even death, etc...
Allah forgives you and pardons you, but you should not use this as a covering for swearing too much in the book of allah swt. fear allah and never do it again unless its very necessary for reasons such as those mentioned above. This is my opinion and understanding of the holy Quran. may allah forgive us all.