Printer wireless network

[Su-2511]

Hi. I'm going around in circles here! I moved my computer and printer into the house while my garden office was being refurbished, and was using the home broadband for work and printing - no problem.

However, I have now moved back in and reconnected to my office mobile wifi dongle, but I can't get the printer to communicate with the computer any longer. The printer information page says the printer is still connected to the wireless network from the  house and I can't seem to change it. 

I've restarted, rebooted the wifi dongle, been through the HP Print and Scan Doctor app, selected the printer in my WiFi Networking and Internet settings and put in the mobile wifi dongle's password - all to no avail.

Can anyone help? TIA

[Su-2511]

As it happens, I have now managed to connect again. I had to wait ages for the HP software to find printers on my network and the one I couldn't connect to said it was offline, but then a more generic printer came up and I was able to create a new setup. I'd still like to know how I could have changed the printer network address back to the original though - I had no trouble when I moved into the house to work!