Strange Pop-Up Asking for My Phone Number After Logging Into My Gaming Account

Last night, I logged into my online gaming account as usual, but right after signing in, a pop-up appeared asking me to verify my phone number for security reasons. The weird thing is, I never enabled phone verification before, and the pop-up looked a bit off - different font and colors from usual. I didn’t enter anything and closed it immediately. I’ve checked my account settings on the official website, and there’s no phone number linked or any new security settings enabled. Also ran a quick malware scan on my PC, which came out clean. I’m worried this might be some kind of phishing attempt targeting gamers. Has anyone else encountered a suspicious pop-up like this after logging into a game? What’s the safest way to confirm if this is legit or just a scam? Should I change my password and enable two-factor authentication right away?