People frustrate me

I work at the front and I was helping this guy who was using health insurance to pay for his food and it only covered like 70% of his transaction and he kept on asking me like why it only covered some and I had to tell him there’s probly a limit on how much you can buy per item in one thing because it doesn’t show on my screen what wasn’t covered. he just didn’t believe me so he just stared at the total for like 5 min waiting for me to do something as if the total was just gonna disappear. I offed to scan the items to see what wasn’t covered and he was just like I need everything and I was like okay and let him wait to see if he would find another payment method. Like I swear at one point he thought I was gonna pay for the rest of his stuff😭. I ended up getting my TL and she told him the same thing and was just like okay cuz at this point he’d been in the line for like 20 min just sitting there shocked that it didn’t cover everything. I ended up having to leave my register because I explained to him like 5 times the same thing over and over and I already had a long day. I swear Walmart needs to update their system because the amount of times I’ve had to tell people paying with insurance or ebt that I do not know what was and what wasn’t covered or that their thing declined is insane to me.