This is the message from adsense team:
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Hello,

Thank you for your interest in Google AdSense. Unfortunately, after
reviewing your application, we're unable to accept you into AdSense at
this time.

We did not approve your application for the reasons listed below.

Issues:
- Contact address incorrect, incomplete or not provided
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Okay, not much problem with changing the contact address right?
Well I did that 5 times already and I keep on receiving the same message again.

Then this other message highlighted in yellow in step 1 caught my attention:
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Thank you for your continued interest in AdSense. Please update your account information below and resubmit.
If your application was not accepted due to issues with your website, please make sure that you have resolved them before resubmitting.
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Does this message mean it's a website issue for sure or it's just saying? Because I haven't received any official notice that there's a problem with my website.