By Barbarak
North Yorkshire,
United Kingdom 
Id please. I think this is a weed/wildflower. It had a prostrate habit spreading out over the ground from a central stem. I dug it out but then found a blank plant label. I put the root and stems into water to await further info. Suggestion from a friend was campion, but I haven't seen it as ground hugging.
26 Apr, 2020
Answers
Thanks . Not wanted in the particular area of my garden even though pretty pink flower. Could go behind the shed I suppose for the bees.
27 Apr, 2020
Good idea if you can. I have some that 'fall' over and then right themselves at the tips so they look as if they are ground hugging. I have an area in the garden for them too. Large White and orange tip butterflies like them a lot. its one of their food plants.
27 Apr, 2020
looks like red campion to me, certainly looks similar to mine.
26 Apr, 2020