diff --git a/firmware/application/src/app_cmd.c b/firmware/application/src/app_cmd.c
index f584746..947b165 100644
--- a/firmware/application/src/app_cmd.c
+++ b/firmware/application/src/app_cmd.c
@@ -791,6 +791,7 @@ static data_frame_tx_t *cmd_processor_mf1_read_emu_block_data(uint16_t cmd, uint
 }
 
 static data_frame_tx_t *cmd_processor_mf0_ntag_write_emu_page_data(uint16_t cmd, uint16_t status, uint16_t length, uint8_t *data) {
+    uint8_t byte;
     uint8_t active_slot = tag_emulation_get_slot();
 
     tag_slot_specific_type_t active_slot_tag_types;
@@ -800,11 +801,14 @@ static data_frame_tx_t *cmd_processor_mf0_ntag_write_emu_page_data(uint16_t cmd,
     // This means wrong slot type.
     if (nr_pages <= 0) return data_frame_make(cmd, STATUS_INVALID_SLOT_TYPE, 0, data);
 
-    if (length < 2) return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &nr_pages);
+    if (length < 2) {
+        byte = nr_pages;
+        return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &byte);
+    }
 
     int page_index = data[0];
     int pages_count = data[1];
-    int byte_length = (int)nr_pages * NFC_TAG_MF0_NTAG_DATA_SIZE;
+    int byte_length = (int)pages_count * NFC_TAG_MF0_NTAG_DATA_SIZE;
 
     if (pages_count == 0) return data_frame_make(cmd, STATUS_SUCCESS, 0, NULL);
     else if (
@@ -812,7 +816,8 @@ static data_frame_tx_t *cmd_processor_mf0_ntag_write_emu_page_data(uint16_t cmd,
         || (pages_count > (((int)nr_pages) - page_index)) 
         || (((int)length - 2) < byte_length)
     ) {
-        return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &nr_pages);
+        byte = nr_pages;
+        return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &byte);
     }
 
     tag_data_buffer_t *buffer = get_buffer_by_tag_type(active_slot_tag_types.tag_hf);
@@ -824,6 +829,7 @@ static data_frame_tx_t *cmd_processor_mf0_ntag_write_emu_page_data(uint16_t cmd,
 }
 
 static data_frame_tx_t *cmd_processor_mf0_ntag_read_emu_page_data(uint16_t cmd, uint16_t status, uint16_t length, uint8_t *data) {
+    uint8_t byte;
     uint8_t active_slot = tag_emulation_get_slot();
 
     tag_slot_specific_type_t active_slot_tag_types;
@@ -833,14 +839,18 @@ static data_frame_tx_t *cmd_processor_mf0_ntag_read_emu_page_data(uint16_t cmd,
     // This means wrong slot type.
     if (nr_pages <= 0) return data_frame_make(cmd, STATUS_INVALID_SLOT_TYPE, 0, data);
 
-    if (length < 2) return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &nr_pages);
+    if (length < 2) {
+        byte = nr_pages;
+        return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &byte);
+    }
 
     int page_index = data[0];
     int pages_count = data[1];
 
     if (pages_count == 0) return data_frame_make(cmd, STATUS_SUCCESS, 0, NULL);
     else if ((page_index >= ((int)nr_pages)) || (pages_count > (((int)nr_pages) - page_index))) {
-        return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &nr_pages);
+        byte = nr_pages;
+        return data_frame_make(cmd, STATUS_INVALID_PARAMS, 1, &byte);
     }
 
     tag_data_buffer_t *buffer = get_buffer_by_tag_type(active_slot_tag_types.tag_hf);