I recently moved to a foreign country and I made a small group of friends using a Whatsapp group chat. I also happened to have birthday next month after I moved here and invited them all. Since I am not close friend to anybody, nobody bought me a present but she still bought me a present and I was very grateful to her to receive at least one birthday present.
Now her birthday was recently and to prepare myself I bought her a present (nothing big). On her birthday, I learnt she is not celebrating it because she is having exams and probably going to celebrate later. It's been a month and doesn't look like she is going to celebrate this year.
Since it is just a social group, we usually meet at public places. I have never yet visited her, nor know her address, so I cannot parcel the present.
What would be an appropriate way to give the present to her to express my gratitude?