7:11

It's unsurprising that you notice 7:11 on the clock because it's your birthday. Many people notice numbers that have personal meaning or emotional significance. Why You Start Seeing Certain Numbers Again and Again talks about why that is.

When you started wondering if it meant something more than just noticing it, it then became a mystery. And you started seeing 7:11 more and more often, even creeping you out. Why People See Certain Numbers All the Time explains how that works.

In addition to numbers with personal meaning or emotional significance, numbers that attract attention with certain patterns, such as numbers with all the same digits (like 3:33) or numbers with sequential digits (like 12:34), can also attract enough attention with their uniqueness to make them remembered. And, if seen again, might cause a person to wonder what it means. In which case, as described, a person will start seeing the numbers more often.

There is unlikely to be a reason for seeing the numbers other than you're seeing them. The reason you keep seeing the numbers again and again is most likely because you wonder if there's more meaning to the seeing than just that you're seeing them.

There really may be a personal reason you're seeing the numbers. If you believe there is, you're likely to keep seeing the number until it's resolved. Unfortunately, I'm not aware of any way to use numerology for calculating personal reasons that may relate to something beyond the numerology meaning of the numbers being seen.