YOU SAID:

I'm getting bored at a conference

INTO JAPANESE

私は会議で退屈しています

BACK INTO ENGLISH

I am bored at the meeting

INTO JAPANESE

私は会議に退屈しています

BACK INTO ENGLISH

I am bored in the meeting

INTO JAPANESE

私は会議に退屈しています

BACK INTO ENGLISH

I am bored in the meeting