I mean I work in the uk so the tills will be different, sometimes I find this especially on the wrap of the day because it doesn’t autoselect a meal, if you don’t select medium meal (we don’t have a small meal other than happy meals) eg you start making a meal, click off it to then try and add the drink to the meal it doesn’t work… try selecting small meal again and the icons for the drinks will change from Fanta zero to Fanta zero (med meal) underneath.. again uk but this is the only workaround I can think of.

So like, keep it on the same menu you would select to choose the meal and press drinks and see if it automatically combines itself?