I changed my phone and SIM so when I try to log in to Snapchat it sends a (verification) code to the old sim. Problem is I don't have the old sim anymore with me. I don't know how I can recover/verify my account. Please help me. Thank you!
You can recover your account by resetting the password through email. There is a page set up by Snapchat developers where you can request the password to your account through email. This is specified in the recovery text presented on the support page.
Use the following link and read the instructions carefully: https://support.snapchat.com/en-US/co/sms-reset