can not have long conversation after some days

Why are you trying to date some girl in your school if you already have a girlfriend?

No it was my problem with my girlfriends. and i trying to that girl in university.
i am alone now...
really i don't know what topics is fine for long talking

Im not even sure how to respond to this. I usually dont go into conversations with set topics or limit myself to certain subjects.

I just ask questions about the person Im talking to and share related responses. I dont shoot for anything other than learning about them and discovering their interests in a fun way.

But if you really insist on a subject why not discus the cofriction of super fluids?

Dear Krumple,
i really can not continue a conversation over 1 hour! i did it with my first love i can't now!
that problem is more after a few days of our relationship.
i don't answer their message because i know after response i should more talking and i don't have any idea!

Out of curiosity, let me ask an obvious question: are you conversing to them in English or your native language?