I Have a double url !!! and need help to fix it…

Hi
If you can help with this I would be grateful…

My site is https://invest-in-overseas-property.info/

And I set it as a static page and when I add another page I get a “double url” like this

https://invest-in-overseas-property.info/invest-in-overseas-property/property-investment-opportunity-in-the-usa/

OR

https://invest-in-overseas-property.info/invest-in-overseas-property/more-overseas-investment-opportunities/

Obviously I have done something wrong but I don’t know what…anyone know how I can fix this ?

Thanks