It is very common. In my experience, you should expect 84 out of 100 messages to be ignored. What I really cannot understand is why people who write in their profiles that they are looking for a language exchange ignore the messages.

Just try not to send simple message to show your interest to become their language partners only, instead, you may send more relevant words to illustrate your motive, interest, reason, date and ways to the person you wish to practice with.

For example, I prefer to say: "My name is Allen and have read some of your writing. I suppose you have time on this saturday to practice your desired language with me." instead of "wishing to be your language partner" which does not make too much sense in my opinion.

@Momochan,

But do not you think it is a bit impolite to ignore someone who contacts you? I do not mean responding to silly request like 'Hello, I want to be your language partner' (especially when the person is not learning your native language). I mean when you send a message introducing yourself and explaining what you can offer and what you expect to get in exchange.

Hello Hasan,

Some people might be already satisfied with their existing partners or just not available by lessons from italki teachers with paying money. Don't be disappointed and keep on contacting. Good luck.