What to do if you have put too many things on instalment and your monthly repayment is so high it eats into your savings and at the end of each month you don't have savings at all?

Downgrade to 'frugal' for 1 year and see, whether You're missing something.

Surely currently not sustainable expenses, change possible, however.

good luck !

Since you can't change your monthly instalment and repayment, the only way is to get a side job or decrease your expenses. Look at your monthly expenses and reduce any thing that you do not need.

Stop buying stuff.

This is a sign of poor planning.

I do not encourage to pay by monthly instalments simply because one pays more due to the interest incurred. It is more prudent to buy only what you can afford.