Hallo,
I could really use some advice right now. I borrowed £250 last month (June) to cover some unexpected stuff and was supposed to pay back £300 on the 15th of July (payday). But I’ve had a few surprise bills pop up, and now I’m struggling to figure out how I’m going to repay it on time.
Has anyone been through something similar? Should I try to talk to the lender and work out a payment plan, or is there something else I can do to avoid late fees or extra charges? I’m feeling a bit stuck and would appreciate any tips or suggestions!
In anticipation
It’s crucial to closely read your loan agreement or get in touch with your lender to decide the best course of action. 
They can offer you detailed advice on what to do with the surplus payback amount.
If early repayment is permitted by your loan agreement, you can spend the extra £50 to settle the balance in full. You would avoid paying interest going forward.
The extra £50 may be used to pay interest accumulated until the repayment date if the interest rate specified in your loan agreement exists. This would lower the total cost of your loan.
You could inquire with the lender about the possibility of applying the extra £50 against the principal of a future loan if you intend to take out another one. This would essentially lower the amount that you would have to borrow.
The lender could be willing to give you back the excess amount under certain circumstances. This is less typical, though, and would rely on the details of your loan contract.