missing TCP traffic using wireshark, on a wifi external usb adapter in monitor mode

I am using an ESP32-C6 running a small http server, connected with an OpenWRT AP without security (open , but I had same result when using WPA2, thereby capturing the handshake). 2.4 GHz only. I've set up an Alfa AWUS036NHA wifi adapter in monitor mode on raspberry pi 4 running Kali Linux 2024.3 (kernel 5.15.44, aircrack-ng RTL8814AU driver), to sniff on the channel (11). I can see all UDP traffic, but no TCP traffic. I see the DHCP address being assigned, but that is about the only direct messages I see towards the ESP32. When I execute a request towards the webserver with postman (GET) from

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