diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
index 101f571b027f..3b82c9de26c5 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/mac.c
@@ -798,7 +798,8 @@ mt7925_mac_write_txwi(struct mt76_dev *dev, __le32 *txwi,
 	val = FIELD_PREP(MT_TXD1_WLAN_IDX, wcid->idx) |
 	      FIELD_PREP(MT_TXD1_OWN_MAC, omac_idx);
 
-	if (band_idx)
+	/* 0xff means BAND_AUTO to the firmware, and TGID cannot encode it */
+	if (band_idx && band_idx != 0xff)
 		val |= FIELD_PREP(MT_TXD1_TGID, band_idx);
 
 	txwi[1] = cpu_to_le32(val);