If you're trying to capture HTTP packets to/from your own device, then you should be able to achieve that without a problem. If that's the case, please provide more context as @grahamb suggests.
But if you're trying to capture HTTP packets destined to another device, then your capture setup is probably lacking, in which case I'd advise you to read the information available at the Wireshark wiki page, WLAN (IEEE 802.11) capture setup.
Lastly, it may be that HTTP packets are not being sent at all, but rather it's encrypted HTTPS traffic. Try capturing or looking for traffic on port 443 instead of port 80 - the default ports for HTTPS and HTTP, respectively.
Can you give some more context as it works for me? What packets, if any do you see?
If you're trying to capture HTTP packets to/from your own device, then you should be able to achieve that without a problem. If that's the case, please provide more context as @grahamb suggests.
But if you're trying to capture HTTP packets destined to another device, then your capture setup is probably lacking, in which case I'd advise you to read the information available at the Wireshark wiki page, WLAN (IEEE 802.11) capture setup.
Lastly, it may be that HTTP packets are not being sent at all, but rather it's encrypted HTTPS traffic. Try capturing or looking for traffic on port 443 instead of port 80 - the default ports for HTTPS and HTTP, respectively.