You should have received an email and a message with more info in Creator Studio. Take a look at the detailed resources and note that you can always reapply for the YouTube Partner Program again in 30 days.
I have over 100,000 hours of viewing. I deleted more than 1,000 videos from my channel 8 months ago. Because every time a request was made it was said that videos I deleted more than 10 that are not settled, while they were settled.