I am unable to connect my iPad Pro 5th gen to Wi-Fi after resetting network settings

While browsing on my Mac Mini, I was wanting to open a web page on my iPad5. Both in my office. I did this by "Move to iPad (5)" halfway down the 'Window' menu. The new web page opened on the iPad BUT it had disconnected itself from the wifi. Whilst trying to get it connected, something happened which then prevented me from connecting to the wifi network. I then tried 'Reset Network Settings', but then made a mistake when inputting the network password. Since then I have restarted the iPad twice and tried 'Reset Network Settings' again but the iPad still says 'unable to connect to wifi network'. Connected to the router, there are 3 networks in the house all with the same password. I am able to connect to the other 2 networks but not to the one I want in the office. Does anyone know how to deal with this problem? Thanks for any suggestions.

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