multiple names which one is correct; i, ii, iii or iv?

Hi, Name merging time. I seem to have 4 names.... Name I is quite old and also shared with an actor who has no other credits on imdb. I'm not sure if I 'own' the Name I or she does - I can't find anything else out about her. Name II is correct, but has just 3 credits. Name III is the most filled out and correct. Name IV is 1 credit that is wrong and needs deleting. How do I know which name is mine? Or even is this a thing? I've started the probably lengthy process by requesting a merge from II to III. I then want to merge III into I and delete the actress credit. Is this possible? And then totally delete IV. And then finally change my name so that it included my middle name. Can someone give me tips please. Especially on the who 'owns' the Name I issue? Thanks. Ash Ashley Briggs I, II, III and IV.