@jurassicdave86
Seems like Vodaphone may use Channel 13 in the 2.4Ghz settings as default. You will need to configure the 2.4Ghz wireless settings to use a wireless channel between 1 and 11. Looks like you may have to download the Vodaphone App to make these changes. If you are unable to change the wireless channel through the App or router/dongle, then you will need to purchase a seperate access point (router/extender), configure the proper wireless channel on it (again, 1-11), and set it to "Access Point" mode.
Here is a link to Vodaphone forum with this info. Look around there and post back with an update if helpful or need more help. Post back with your Roku Express model number. (only new Express 4k/4k+ models are capable of using both 2.4 and 5Ghz band, all other Express models can only see/use 2.4Ghz band)
https://forum.vodafone.co.uk/t5/Broadband-connection/Can-t-connect-internet-to-Roku-or-Firestick-Pho...
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