In the customer list of transactions, why some transactions appear as payment, are negative and marked as closed and other are Payments, negative and closed?

I know some explanation as to why this is happening on your end, feprimafi.

If the amount is located within the customer's profile, the payment is commonly displayed as a negative amount and closed since this is already applied to an invoice to zero out the balance. In addition, if you have a payment transaction that indicates a negative amount and Unapplied status, it means that the payment is not linked to the open invoice. 

To link the Unapplied status to the open invoice here's how: 

1. Go to the +New located at the top left corner. 
2. Under the Customers column, click the Invoice option. 
3. Fill out the necessary field.
4. To link the Unapplied payment, choose the same customer under the Customer dropdown.
5. The amount should be equal to the Unapplied payment. 
6. Once done, press Save or Save and close. 

After doing this, you'll see if the amount is already applied by seeing the Closed status with the negative amount. 

Regarding the voided transactions, you can run the Audit log to see when and who voids these transactions. 

Here's how: 

1. Go to the Gear icon at the top right corner and click Audit log.
2. Choose the User and Date.
3. Under the Events dropdown, choose according to your preference. 

After this, the data will show the events/transaction according to what you've chosen in the User, Date Changed or Events. 

Furthermore, you can also learn more about void or deleted transactions. 

If you need further assistance or you have some information to share, just leave them in the comment section. I'm always around to help.