Cand wearing a Toppik fiber after a hair transplant damage your grafts?

Hello ,since 4 weeks i had the second hair transplant. I work one job where i have contact with a customer and i have used toppik hair fiber since 6 month. Now i want to work again but i need to cover my scalp with any cap or any fiber hair but doctor from the second surgey doesnt allowed me to use ,he said that toppik hair fiber can damage your graft and can be problem with your results. I want to ask you can be that fiber toppik have any side effeckt or damage your hair transplant. Thank you !