diff --git a/controllers_v2/invoice.ctrl.go b/controllers_v2/invoice.ctrl.go
index b595ad3..977802e 100644
--- a/controllers_v2/invoice.ctrl.go
+++ b/controllers_v2/invoice.ctrl.go
@@ -44,7 +44,7 @@ type Invoice struct {
 // @Description  Returns a list of outgoing payments for a user
 // @Accept       json
 // @Produce      json
-// @Tags         Account
+// @Tags         Invoice
 // @Success      200  {object}  []Invoice
 // @Failure      400  {object}  responses.ErrorResponse
 // @Failure      500  {object}  responses.ErrorResponse
@@ -87,7 +87,7 @@ func (controller *InvoiceController) GetOutgoingInvoices(c echo.Context) error {
 // @Description  Returns a list of incoming invoices for a user
 // @Accept       json
 // @Produce      json
-// @Tags         Account
+// @Tags         Invoice
 // @Success      200  {object}  []Invoice
 // @Failure      400  {object}  responses.ErrorResponse
 // @Failure      500  {object}  responses.ErrorResponse
@@ -184,7 +184,7 @@ func (controller *InvoiceController) AddInvoice(c echo.Context) error {
 // @Description  Retrieve information about a specific invoice by payment hash
 // @Accept       json
 // @Produce      json
-// @Tags         Account
+// @Tags         Invoice
 // @Param        payment_hash  path      string  true  "Payment hash"
 // @Success      200  {object}  Invoice
 // @Failure      400  {object}  responses.ErrorResponse
diff --git a/docs/docs.go b/docs/docs.go
index 4d28496..a89c936 100644
--- a/docs/docs.go
+++ b/docs/docs.go
@@ -175,7 +175,7 @@ const docTemplate = `{
                     "application/json"
                 ],
                 "tags": [
-                    "Account"
+                    "Invoice"
                 ],
                 "summary": "Retrieve incoming invoices",
                 "responses": {
@@ -218,7 +218,7 @@ const docTemplate = `{
                     "application/json"
                 ],
                 "tags": [
-                    "Account"
+                    "Invoice"
                 ],
                 "summary": "Retrieve outgoing payments",
                 "responses": {
@@ -261,7 +261,7 @@ const docTemplate = `{
                     "application/json"
                 ],
                 "tags": [
-                    "Account"
+                    "Invoice"
                 ],
                 "summary": "Get a specific invoice",
                 "parameters": [
@@ -490,7 +490,8 @@ const docTemplate = `{
             ],
             "properties": {
                 "amount": {
-                    "type": "integer"
+                    "type": "integer",
+                    "minimum": 0
                 },
                 "description": {
                     "type": "string"
@@ -651,9 +652,6 @@ const docTemplate = `{
                 "fee": {
                     "type": "integer"
                 },
-                "payment_error": {
-                    "type": "string"
-                },
                 "payment_hash": {
                     "type": "string"
                 },
@@ -695,9 +693,6 @@ const docTemplate = `{
                 "fee": {
                     "type": "integer"
                 },
-                "payment_error": {
-                    "type": "string"
-                },
                 "payment_hash": {
                     "type": "string"
                 },
diff --git a/docs/swagger.json b/docs/swagger.json
index 1f3ad19..06f1720 100644
--- a/docs/swagger.json
+++ b/docs/swagger.json
@@ -171,7 +171,7 @@
                     "application/json"
                 ],
                 "tags": [
-                    "Account"
+                    "Invoice"
                 ],
                 "summary": "Retrieve incoming invoices",
                 "responses": {
@@ -214,7 +214,7 @@
                     "application/json"
                 ],
                 "tags": [
-                    "Account"
+                    "Invoice"
                 ],
                 "summary": "Retrieve outgoing payments",
                 "responses": {
@@ -257,7 +257,7 @@
                     "application/json"
                 ],
                 "tags": [
-                    "Account"
+                    "Invoice"
                 ],
                 "summary": "Get a specific invoice",
                 "parameters": [
@@ -486,7 +486,8 @@
             ],
             "properties": {
                 "amount": {
-                    "type": "integer"
+                    "type": "integer",
+                    "minimum": 0
                 },
                 "description": {
                     "type": "string"
@@ -647,9 +648,6 @@
                 "fee": {
                     "type": "integer"
                 },
-                "payment_error": {
-                    "type": "string"
-                },
                 "payment_hash": {
                     "type": "string"
                 },
@@ -691,9 +689,6 @@
                 "fee": {
                     "type": "integer"
                 },
-                "payment_error": {
-                    "type": "string"
-                },
                 "payment_hash": {
                     "type": "string"
                 },
diff --git a/docs/swagger.yaml b/docs/swagger.yaml
index 7d83b9d..6c451cd 100644
--- a/docs/swagger.yaml
+++ b/docs/swagger.yaml
@@ -28,6 +28,7 @@ definitions:
   v2controllers.AddInvoiceRequestBody:
     properties:
       amount:
+        minimum: 0
         type: integer
       description:
         type: string
@@ -135,8 +136,6 @@ definitions:
         type: string
       fee:
         type: integer
-      payment_error:
-        type: string
       payment_hash:
         type: string
       payment_preimage:
@@ -164,8 +163,6 @@ definitions:
         type: string
       fee:
         type: integer
-      payment_error:
-        type: string
       payment_hash:
         type: string
       payment_preimage:
@@ -302,7 +299,7 @@ paths:
       - OAuth2Password: []
       summary: Get a specific invoice
       tags:
-      - Account
+      - Invoice
   /v2/invoices/incoming:
     get:
       consumes:
@@ -329,7 +326,7 @@ paths:
       - OAuth2Password: []
       summary: Retrieve incoming invoices
       tags:
-      - Account
+      - Invoice
   /v2/invoices/outgoing:
     get:
       consumes:
@@ -356,7 +353,7 @@ paths:
       - OAuth2Password: []
       summary: Retrieve outgoing payments
       tags:
-      - Account
+      - Invoice
   /v2/payments/bolt11:
     post:
       consumes: