iPad and iPhone no longer recognize Epson ET-2850 printer

As your printer supports AirPrint - and assuming that AirPrint was correctly set-up and working as expected prior to recent iPadOS updates - you may find that restart of your network components will resolve printing problems. You’ll need to restart your network devices in the correct order.

Assuming that you WiFi Router provides DNS services for your network, restart devices in this order - allowing time for devices to fully boot/restart prior to restarting other devices:

• WiFi Router
• Upstream wired Network Switch(es) (if any)
• WiFi Access Points / Network Extenders
• Other fixed infrastructure devices - such as Printers
• Client devices (your iPad)

Restarting your iPad and iPhone after restarting other devices in the correct sequence, is most simply achieved by a forced-restart of the device:

Force restart iPad - Apple Support

Force restart iPhone - Apple Support

If you continue to have difficulties, check to see if your iPad is using the new WiFi Private Address feature. This feature is intended to provide additional privacy and security when using “public” (untrusted) WiFi networks.

Settings > WiFi > [Your WiFi Network / SSID] - tap the “i” icon - Private Address

The Private Address feature is largely unnecessary for your home WiFi network; if enabled, Private Addressing can interfere with anticipated operation of other devices, such as AirPrint/Airplay. In such circumstances, you may need to disable this feature - and can be enabled or disabled for each individual network.

Use private Wi-Fi addresses in iOS 14, iPadOS 14, and watchOS 7 - Apple Support

Don't forget that AirPrint only supports the print functions of your Epson multi-function printer. Whereas your Windows PC requires that you install the appropriate print-drivers for your Epson printer, for your iPad and iPhone, scanning and other printer functionality requires installation of the appropriate Epson companion App(s) from the Apple App Store.