I would just replace them if possible.
You could try a thick paste of baking soda and water, and let it sit over night then clean it with vinegar. Silicone does absorb odors thought so you might have to replace it. And when you wash it be sure you’re rinsing it thoroughly with very hot water
I switched to stainless steel baby plates! So much safer and cleaner.
@Mara how are they safer? I thought that silicone was safe 🙃
Recently they published some articles about how silicone isn’t temperature safe
So it can leach chemicals when you freeze it or put hot food on it (or put it in the dish washer)
@Mara thanks for the info
@Mara do you have any brand suggestions?
I just bought some from Amazon. Ahimsa makes some but I found them to be over priced.
Boil it with vinegar and lemon