Hey! For the token to appear in metamask you have to add it. You can do this by going to metamask and at the bottom under assets there will be a section that says, "import tokens." If you click this then you can search for usdc and add it. Also make sure you are on the same chain that you hold the usdc on or else it won't show up. If you go to https://blockscan.com/ you can see the different chains you've interacted with. If you need more help please join the discord.