diff --git a/pm3py/core/hf_iso15.py b/pm3py/core/hf_iso15.py
index 1e5084a..40e3c2d 100644
--- a/pm3py/core/hf_iso15.py
+++ b/pm3py/core/hf_iso15.py
@@ -27,8 +27,12 @@ class HF15Commands:
 
     async def scan(self) -> dict:
         """Scan for ISO15693 tags using inventory command."""
-        # ISO15693 inventory: flags=0x06 (high data rate + inventory), cmd=0x01
-        iso_cmd = bytes([0x06, 0x01, 0x00])  # flags, inventory cmd, mask_len=0
+        # ISO15693 inventory: flags=0x26 (high data rate + inventory + 1-slot), cmd=0x01.
+        # SLOT1 (0x20) is required: without it the firmware runs a 16-slot anti-collision
+        # round and replies with an iso15_slot_result_t struct, not [flags][dsfid][uid],
+        # so this parser would read the struct header as a zeroed UID. 1-slot gives the
+        # simple single-tag response this method expects. Use hf 15 reader --all for many.
+        iso_cmd = bytes([0x26, 0x01, 0x00])  # flags, inventory cmd, mask_len=0
         flags = ISO15_CONNECT | ISO15_READ_RESPONSE | ISO15_APPEND_CRC
         payload = struct.pack("<BH", flags, len(iso_cmd)) + iso_cmd
         resp = await self._t.send_ng(Cmd.HF_ISO15693_COMMAND, payload, timeout=5.0)