Byzantine 20 Nummi Help

Hello!

I am going through my father's coin collection and trying to catalog everything he has. I have one that he was unable to identify but that I was able to identify as a 20 Nummi piece, but I am having trouble dating it. I have attached pictures of the front and back of the coin. My best guess is Justinian, 20 Nummi. The top is a cross, right side is the Greek 6 and I think a cross? The bottom is a gamma(?), which is usually the mint location, but I'm unsure. The left side is probably an ‘ANNO’.

I think it's N#297892 .

Reading the regnal year is another story, to me looks very worn.

Thank you so much!

I tried to get as much contrast as I could when taking the picture, I can tell for sure there's a G on the right side of the K and then something else that may be a cross or may be an I, but at least narrowing down the era is extremely helpful!