Mouse not moving on certain inventory spaces

When I'm playing Minecraft in survival, I use my inventory a lot. I've been noticing recently that when I try to move my mouse over to some of the top right slots, my Minecraft highlighting mouse stops. What I mean is when you hover over a slot in the player's inventory it's highlighted. But when I go to those slots they mouse arrow keeps going but the highlighter stops, therefore I can't retrieve the item. This is only in the players inventory and I have not experienced this bug in inventory blocks like shulker boxes and chest. Originally I thought this was lag but even when I disconnected and reconnect it still didn't work. But sometimes randomly it does.