
Hi @Brijendra Gautam,
Thank you for posting in this community.
According to your detailed description, we do understand how frustrated you are now. However, I feel regretful to tell you that I don't have your problem in my test environment.
Although we can't reproduce your situation, we can work together to narrow down and resolve the situation. So, please kindly provide more information below to let us work further.
1.Are other users with permissions facing the same problem? View through another computer or account.
2.Whether all site pages have the same problem? You could create a new site page to check.
3.Check if the same issue occurs with other SharePoint site collections.
4.You could try to clear browser cache then restart it.
5.Try to use a different browser or your browser's InPrivate mode to see if the same error occurs.
6.If the problem persists, please describe to me the details of how you created the site pages, perhaps there is something wrong with the process of creating the pages. Please be careful not to disclose your private information.
Thank you for your time and efforts in advance.
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