When viewing a Recurring Gift Pay-Cash record, it's possible to check the original Recurring Gift it is linked to, by clicking on the dropdown arrow ('Go To') in the toolbar.

This dropdown shows you the Constituent record, as well as a quick link to the linked Recurring Gift record.

The Gift Amount that is mentioned next to this linked Recurring Gift record shows the Gift Amount of the current Recurring Gift Pay-Cash record you have open, instead of the actual linked Recurring Gift record (which also has the Schedule, Transactions, Amendments).

It's more logical that the Gift Amount show there is the actual Amount for the Recurring Gift, that way you can quickly see a difference between the Pay-Cash Gift you're adding/linking and the Recurring Gift itself.