You will not like the answer but it's yes and no, and here is why.
Yes, it appears a relationship exists, but no you need to dig deeper. What does that mean? TRIANGULATION. You found a match. Now the hard work. To prove a relationship exists, you must triangulate. What does that mean? You match this person on chromosome (?/23) at beginning and ending no's what? You and your match must find another person who matches you in the same (Overlapping) area on the same chromosome; and that same match would have to match your original person in the same partial overlapping area. All three people must match one another on the same chromosome and match each other in same overlapping area. This would definately show you are related to this person. Once you know by how many total cM's you can then try to figure out how your MRCA or Most Recent Common Ancestor is. USE DNA PAINTER to see the cM's and all possibilities. If you both have trees then it should not be too difficult. If you know your 3rd set of GGrandparents for both of you you are well on your way to proving your relationship. Work together if you can to solve the clue you are given with matching DNA.. One thing to keep in mind is that certain chromosome areas are considered dumping areas and lots of conflicting or false positive's are associated in these areas. Of course the longer the strand of DNA you have associated with your match, the more certain a relationship exists. If you were to lower the cM's to say 3 and therefore look for any strand that is 3 cM or more, your match list would expand greatly, but this brings in the false positives. 7cM is really the lowest so that these false positives don't lead one to chase their tail so to speak. 10cM's is really a great way to get rid of almost all false positives and you have a better than 50% chance of matching without doing any research. Hope you find this helpful.
DNA Painter suggests at 389cM
73%Great-Great-Aunt / Uncle Half Great-Aunt / Uncle Half 1C 1C1R Half Great-Niece / Nephew Great-Great-Niece / Nephew