How to make bf feel loved?Watch
The case that is not so good is if he's coming across needy. If you are busy but still do your best to spend what free time you have with him and it still isn't enough that sadly that is on him. Some people need a lot to feel loved and that's what makes them needy, it comes from a deeper anxiety/insecurity. In this case I'd talk more deeply about it to him and ask him what you can do to help him through that.
Hopefully it is the first case I described and not the second. Just give him some priority in your life, maybe take a day off to spend with just him and do something out of the ordinary together.
If you’re both busy then it would definitely be something that comes to mind in terms of making time for each other, fix it before it’s too late.
You might not know that you’re doing the things which make him unloved.