www.taxcalc.eu suggests that your take home should be nearer €3,800. Can you clarify the details of your payslips perhaps? Are you sure that you are claiming all relevant tax credits? Does the €3,500 figure reflect additional deductions such as
CU repayments? Are you making pension repayments too by any chance?
What rates of interest apply to your various debts? Have you stopped using credit to fund your normal outgoings?
What are the details of your mortgage - original amount and term, outstanding amount and term, rate, rate type (fixed, variable, tracker), property value etc.?
Why did you rack up that amount of unsecured debt?