You left because you were made redundant when the company folded.
Most employers understand when the company you worked for has closed. Be as honest as possible, nobody likes surprises.
If so the period worked and reasons for leaving the organization
Tell management that they're bad
If you still owe them money then they can change the interest rate, providing they are changing it for everyone and not as a penalty for leaving.
You need to write that you left because you no longer wanted to work for the company. As long as there are a mutual agreement, there is no reason to explain more about it.
Plant closed
Any lender has the right to sue regardless of the reason if you choose not to pay them back. Leaving a state where you took a payday loan is not a reason for a payday lender to sue you - not paying them back is.
A closed system is one where there is no mass entering or leaving the system.
Something like "It was discovered that the company was becoming less stable financially, so I decided it was better to leave before they went out of business"
Most employment is called 'at will'. This means either party has the option to terminate employment at any time and for any reason. You certainly could choose to leave your company.
AstraZeneca is one of the major Indian company to have closed down. The company was a major pharmaceutical company.
On your resume you only put the dates that you worked regardless of why you left. You only need to give that information on the application when they ask "reason for leaving". Your options are bankruptcy, company moved, location closed, or position eliminated. That should cover virtually all good reasons. Try to avoid fired or discontent.