I am sorry it is triggering for you. Can you just put it away somewhere and just say a simple thank you to the person. It was likely meant with good intention and is neither your fault nor theirs that its triggering for you. But you can take care of yourself by putting it away somewhere where you don't have to be triggered by it anymore.
I have received very triggering gifts from people before, some that were very inappropriate. Once as an adult my ex step father gave me a (very inappropriate and might be very triggering)

for Christmas which I unwittingly opened in front of my entire extended family. Why he ever thought that was appropriate I'll never know.
How did I respond? I don't even know, I dissociated it of course. I only remembered that years later and other family members remembered it too, so at least I know that was real.
Just take care of yourself. Put it away. I'm sorry it was hard for you.