Question about LoRa setSyncWord Option

Hi, i'm working on a LoRa Project and use the receive mode . I tried to set a specific sync word
but still get too much messages from other sender. Then i changed (for a test) the sync word on my sender side, but the receiver still receives these messages. I checked register 39 and i can see the
syncword really changes. So what can be wrong ?

You cannot use the sync word to filter, with 100% certainty, packets between TX and RX.

Some sync words will reduce RX sensitivy and some combinations will work, regardless of TX and RX using different ones, but you have already discovered this.

Best to stick to the standard syncwords.