My boyfriend doesn't like to kiss me?

First of all, sorry for any mistakes. English is not my first language.

So the thing is I'm a really touchy person and I like to give my partner a lot of physical affection. Right now I'm in a relationship with some who also likes that. The problem is that recently he started to avoid/reject direct kisses on the mouth. (Everywhere else is fine). At first I thought it was because I had bad breath or because my lips are often a bit dry since it wasn't like this in the beginning. But this has been going on for a few days now. (I'm currently living with him for 2 month because we live in different countries and had a long distance relationship but visited each other occasionally)

I asked him about this multiple times and he just told me that he doesn't feels like it right now, which I understood in the beginning. I have to admit it made me a little bit sad because I like kissing him and showing him affection that way. Right now I don't get any kisses from him at all (at least on the mouth, the rest stayed the same) and when I asked if it's ok to kiss him the answer is mostly no.

What am I supposed to do? I know the right thing is to be understanding but it makes me feel a bit unloved and lonely and I really miss kissing him. I just wish it would be like it used to be.