Birthday Candles and MWS

I have MWS and understand the cake topper must be removed for certain actions to happen like cutting the cake, I think.  

I gave up on weddings so I don't know too much about cake glitch interactions but now my birthday cakes aren't working.  

With the candles placed and the cake placed centered I couldn't get my sims to blow out candles or help another younger sim. I have aging off so I age them when I'm ready with a birthday but now I can't use the "blow out candles" option? I eventually gave up and just did the aging in CAS but is MWS creating an issue with birthday cakes? 

It was a standard white base game cake. Are the candles considered a topper? Are sims rejecting the prompt as if the candles should be removed?