Hi,
You may want to try a full power-cycle sequence:
Power off the Wi-Fi router, the printer, the iPhone and the iPad, and all other computers and devices. Wait two to three minutes. Power on the router. Wait two to three minutes. Power on the printer. Wait a minute or two. Power on the iPhone and the iPad. Finally, power on all other computers and devices.
Also, your Canon printer appears to connect via 2.4 GHz. Modern multi-band routers may have automatic ("smart") device discovery and band selection. If there is a problem, it may be necessary to change settings and split/rename bands. The following article for Brother printers could perhaps be of some interest: https://help.brother-usa.com/app/answers/detail/a_id/73618/~/compatibility-with-5-ghz,-dual-band-wireless-router,-or-mesh-networks .