Block Snapchat

How can I block Snapchat from my kid’s phone after he already has it? I have already read the Restrict Content Apple replies with. The time limit only allows me to put it down to 1 minute. The allow apps never lists the apps that were downloaded - only the original apps that came on the phone. I’ve already ordered a new phone that doesn’t have internet because Apple can’t help me block apps like Snapchat and TikTok