Lost permission to stay and work in the UK having a debt

[PstM]

I have got some debt in the UK Bank. I am a foreigner but was the UK resident during several years and was allowed to work in the UK because I had work permission. I worked for British company in the UK and had a permanent contract. When my last working permission was expired three months ago my company applied for a new one, but the UK Government Home Office declined the application due to incompatible salary level, as a matter of fact I had to leave the country as soon as possible because I wasn’t allowed to stay there.

I was to suffer an unexpected loss of income and chance to pay back the debt I have, so now I am not able to pay back the debt.

Could anybody advise me please what choice do I have and how I should deal with my bank?