diff --git a/electrum/gui/qml/components/InvoiceDialog.qml b/electrum/gui/qml/components/InvoiceDialog.qml
index c559801cc..a240a632a 100644
--- a/electrum/gui/qml/components/InvoiceDialog.qml
+++ b/electrum/gui/qml/components/InvoiceDialog.qml
@@ -435,6 +435,9 @@ ElDialog {
                 enabled: invoice.canSave
                 onClicked: {
                     app.stack.push(Qt.resolvedUrl('Invoices.qml'))
+                    if (invoice.amount.isEmpty) {
+                        invoice.amount = amountMax.checked ? MAX : Config.unitsToSats(amountBtc.text)
+                    }
                     invoice.save_invoice()
                     dialog.close()
                 }
@@ -446,8 +449,18 @@ ElDialog {
                 icon.source: '../../icons/confirmed.png'
                 enabled: invoice.invoiceType != Invoice.Invalid && invoice.canPay
                 onClicked: {
-                    if (invoice_key == '') // save invoice if not retrieved from key
+                    if (invoice.amount.isEmpty) {
+                        invoice.amount = amountMax.checked ? MAX : Config.unitsToSats(amountBtc.text)
+                        if (invoice_key != '') {
+                            // delete the existing invoice because this affects get_id()
+                            invoice.wallet.delete_invoice(invoice_key)
+                            invoice_key = ''
+                        }
+                    }
+                    if (invoice_key == '') {
+                        // save invoice if new or modified
                         invoice.save_invoice()
+                    }
                     dialog.close()
                     doPay() // only signal here
                 }
diff --git a/electrum/gui/qml/qeinvoice.py b/electrum/gui/qml/qeinvoice.py
index 7188eda36..b60da544e 100644
--- a/electrum/gui/qml/qeinvoice.py
+++ b/electrum/gui/qml/qeinvoice.py
@@ -313,8 +313,6 @@ class QEInvoiceParser(QEInvoice):
 
         self.set_lnprops()
 
-        self.canSave = True
-
         self.determine_can_pay()
 
         self.invoiceChanged.emit()
@@ -339,6 +337,7 @@ class QEInvoiceParser(QEInvoice):
 
     def determine_can_pay(self):
         self.canPay = False
+        self.canSave = False
         self.userinfo = ''
 
         if not self.amountOverride.isEmpty:
@@ -346,6 +345,8 @@ class QEInvoiceParser(QEInvoice):
         else:
             amount = self.amount
 
+        self.canSave = True
+
         if amount.isEmpty: # unspecified amount
             return
 
@@ -652,6 +653,8 @@ class QEUserEnteredPayment(QEInvoice):
             self.validationError.emit('recipient', _('Invalid Bitcoin address'))
             return
 
+        self.canSave = True
+
         if self._amount.isEmpty:
             self.validationError.emit('amount', _('Invalid amount'))
             return
@@ -659,7 +662,6 @@ class QEUserEnteredPayment(QEInvoice):
         if self._amount.isMax:
             self.canPay = True
         else:
-            self.canSave = True
             if self.get_max_spendable_onchain() >= self._amount.satsInt:
                 self.canPay = True