romance option gone sims 4

okay, so heres the thing, the guy im trying to get to have romantic relations with other sims ive created, is adopted. He has the same last name because hes adopted by the girls fathers sister. so i was thinking maybe thats why? but i tried clicking on random ppl in the neighborhood and no romance option came up for strangers either? but its not mods because i recently made a house of 8 men and 8 women so my sims could meet ppl i can control, and i played the womens house for example and had a few other click on other girls in the house and romance option came up, so now i have no idea whats happening... becuase with all my old sims, except ones that are already married or in a relationship it doesnt show for, but then new sims it does... wth is going on lol.

also... ive done this with a son of a distant relative who is now in a relationship with the same guys sister, who was also adopted. she was able to have romance options with her "distant cousin" but her brother the other adopted boy isnt able to do the same thing? is it because it would be his 1st cousin? instead of like 2nd or 3rd cousin? regardless theyre not related but i guess the game sees it differently?

sorry one more thing... i did click on a random woman in the neighborhood with this adopted guy, and there were still no romance options, so its not 100% the whole relative thing.. so now what?