Facial fillers: How much is too much filler?

After fat loss i had a lot of filler put in , but i need to top up every 2/3 months with half syringe as it keep dissolving , i have it in my cheeks, chin and nose to mouth area , those areas still look flat after filler but i am too scared to have FT . Can someone please tell me if filler over time can make my face look worse if too much was put in over the years ? Many thanks