Exchange Vows Grayed Out on wedding arch

Hi, I have discovered that my sims cannot get married on Wedding lots. First of all, when selecting the arch, the "exchange vows" is greyed out (as in the picture) and even if I use the interaction "exchange vows" from the Romantic menu, by clicking on the sim, and even if they complete this interaction, at the end of the wedding they are not married. So I changed the lot type and the interaction exchange vows was visible and accessible again. 

I mention that I use mods, but, in the meantime, I recreated the entire Sims 4 folder and repaired the game and tested the game with and without mods. The result has been the same.  

Another thing that I've discovered is that even if they do everything during the wedding when the exchange vows is functional and the lot type changed, at the end of it they are still engaged. The only solution for this is to place an arch on the residential lot and get them married. Then they receive the certificate and milestones. (PS: I think I have written this in the wrong section of the forum. I've tried to delete it and write it in the Bugs section, but I couldn't) .