Hi, welcome to OpenStreetMap! Thanks for helping to add some detail to your local area! Unfortunately, the source you've used (Herts CC webmap) uses Ordnance Survey maps which are Crown Copyright, which means they cannot be used to help edit OSM in any way. Sadly this means that all the addresses and other names/details you've added from this source will need to be removed. The buildings can stay as I can see they have been traced from Esri. Currently the only way we have for adding addresses in the UK is walking around and entering what we can see. For this I would recommend an app like StreetComplete (android only) which makes it easy to add housenumbers while walking around. Please let me know if you're happy for me to remove these addresses and make some corrections (I would be happy to give you feedback about some things that could be improved.) Thank you.