It's possible that you have a duplicate 'self' on the system and that you're trying to edit your 'other' one. In this case, the system will think you're trying to edit someone else's results and won't let you.
Please check if you have a duplicate on the system and request a merge if so. Once the players are merged, the system will recognise them as you and allow you to edit any of the results.
If this isn't the reason you can't edit your own result then please get in touch and we'll find out what's wrong.