Hi Babu,
Please follow the below steps:-
1. Execute t-code F-30
2. Enter the currency UF and enter the relevant exchange rate (i assume you have maintained the currency ratio as per OB08 with 100 :1 with direct quotation, if this is the case, then enter the rate as 240.654)
3. Then click on choose open items
4. Enter the customer account number
5 click on process open items
6. select the relevant document as mentioned in your message
7. the balance would become zero (or) with some decimal depends on the exchange rate entered
8. you may charge off diff. if it's less than prescribed amount as per your configuration.
9. then you can save so that both the documents would be cleared.
The important thing is you need to enter the correct exchange rate (as per step-2 mentioned above)...as I do not know the ratio & method (direct / indirect quotation) maintained as per your system, I am unable to mention the exact rate.
System basically use the exchange rate mentioned by you as per the initial screen for converting the amount of CLP (your local currency) into UF (foreign currency). If you understand this point, you will be able to achieve this. For more information, please go through the sap help as per the below link:
Clearing Open Items in Foreign Currency - FI Accounts Receivable and Accounts Payable - SAP Library
Hope the above would be useful.