What YouTube team check after you applied for AdSense
1.When you apply for AdSense approval YouTube team checks your main category or niche of your channel. They also check =>
2. Most Viewed videos
3. Newest Videos
4. Metadata (title thumbnail tags and description)
Here I can give you advice that you should not use irrelevant tags, titles, and descriptions. You should not use the description as tags with commas.it will be considered as spamming in the description.
Another thing is that you should read YouTube community guidelines and follow terms and conditions and Google AdSense program policies.
Make videos that should be advertiser-friendly
You must not use inappropriate language, adult content, Harmful and dangerous acts related videos including various controversial issues and sensitive events etc.
Fix YouTube channel monetization under review problem
You go to your Android studio and your feedback is given below.
Hello YouTube team
My channel that takes review has successfully completed 1000 subscribers and 4000 hours of watch time and I have applied to get AdSense approval since 1 month ago. I didn't get any response from you. So I have checked all my videos and didn't find any issues in any videos. Kindly help me to enable monetization in my channel.
Thank you
Then send your feedback and you will get a response from the YouTube team within 24 hours and you can understand why your channel not monetized.
Conclusion
After you send your feedback you will definitely get a response from the YouTube team. Either your channel will be monetized or you will get the error. For example, if you will get an error like reused content. Probably you uploaded videos that do not belong to you. Then you should delete those videos that do not belong to you.