Bit of background, been with my boyfriend for only a month, dating for 3 months. Both mid twenties, no kids.
In person my boyfriend is super loving, affectionate and attentive, the problem is when we're apart. He is notorious for ignoring my texts. He's never been a good texter from the start and would always take a while to respond but always eventually did. This didn't bother me as it allowed me to get on with my day without a distraction. However it's now at the point where he will just point blank ignore my messages. I breezily explained to him how it made me feel trying not to make a massive deal, and he apologised saying it wasn't his intention to make me feel like that but has since continued to do it.
I understand he doesn't like that constant back and forth messaging so I've made a conscious effort not to send pointless chat to him but it hasn't made a difference. I'm now going out of my mind wondering what's going through his 
Any advice on how to approach this? We're still in the early days so I don't want to come across as clingy and naggy ultimately scaring him off, but I feel like it needs to be addressed before it becomes a massive issue.