Why won’t my phone allow me to make a Snapchat account it says it’s due to third-party applications that might be on my phone does anybody know anything about that

I can download the Snapchat application on my iPhone but when I go to create account it won’t let me and it says something about a third party application I don’t know what that is or I’ve tried resetting my phone I’m trying to send you my phone number but every time I create an account it locks my account. I have a Snapchat account on this phone for the first nine ones I had it in one day I just logged me off anniversaries and it won’t let me check I’ll make an account or wouldn’t let me back in miles an account and I was just wondering if anybody else has had that problem or knows how to fix it