disagreements over shared time (M18) (F18), How do i start a conversation regarding this?

My boyfriend and I have been together for about a year. We’re both on summer break with a lot of free time. Because I can get clingy, we previously agreed to one hour of game time a day. Outside of this, we call a bit, but it’s usually right before he takes a nap, so I’m just sitting on the phone with little to no interaction.

Recently, I asked to play a game and he said he was tired, but I later caught him playing with his friends. He then admitted he doesn't think he wants to call daily, but said he wasn't sure what kind of interaction level he actually wants.

The past few days have been a cycle of avoided plans. Two days ago we agreed to play Minecraft, but yesterday he changed his mind, so I let it go. Today I asked again and he said he just got back from the beach and needed to rest, but ten minutes later I saw he was already online playing with his friends. When I asked him about it, he told me to wait while he found a way to ditch his friends, but then he stopped responding. He has a pattern of doing this, where it takes ages to set up a game only for him to leave after 20 minutes.

When I confronted him about the timeline discrepancy, he claimed he just meant he needed time before we played and that I misunderstood. The conversation ended with me pointing out that he was with his friends less than 10 minutes after saying he couldn't play, and him responding that he is a liar and just didn't want me to get mad because he was going to play with someone else, followed by "goodbye."

We have a date planned for tomorrow, but after this interaction, I no longer wish to attend and am seriously considering ending the relationship because I feel he no longer wants to spend time with me.
I need guidance on effective ways to structure a conversation regarding this when one person is consistently avoiding accountability or deflecting.