I updated my Ipad Air 2 to the latest apple update 15/6, now my ipad won't recognize my wifi, how can I get it to work again

Start here:

If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network - Apple Support

…and here:

Recommended settings for Wi-Fi routers and access points - Apple Support

If your WiFi has been set-up according to Apple’s recommended settings, WiFi and Internet connection difficulties are usually an indication that your device does not have a routable IP Address - your IP Address usually being assigned by DHCP. When this occurs, your iPad may only have a self-assigned link-local IP address that begins 169.254.x.x.

If you have a VPN App or profiles installed, or a security App such as Norton, these may be interfering with DHCP and preventing your device from obtaining a valid IP Address for your iPhone hotspot - or the WiFi network to which you are attempting to connect. The resolution is usually simple; if installed, you may only need to temporarily disable or remove the Security App and/or VPN.

DHCP is frequently used to automatically obtain an IP Address. Until your iPad has a valid IP Address to connect to your network, you will not have an internet connection. Disabling or removing VPN and/or the offending security App should allow DHCP to operate normally - allowing connection to your network and the internet.

If this resolves your issue, the VPN and/or security App can be reinstated after the connectivity problem has been resolved.

If your iPhone, iPad, or iPod touch won't connect to a Wi-Fi network - Apple Support

Ringfinder wrote:

Oh by the way, I metal detect in the water and have found over a thousand rings!

I'll tell my fly fisherman buddy. Maybe he'll expand his expertise.

Glad it's resolved. Enjoy your Apple gear.

Good luck with this!

You are very welcome. I’m delighted that the issue was successfully isolated and resolved.