Aha! It appears that I have spotted the issue in your code!
It seems like you are creating pages using the ionic generate command! However, if you take a look at the file structure, you will notice that the page folder has its own module file. You should start by deleting that module file, then proceed to yourPage.ts file and remove the import of IonicPage and also eliminate the annotation of IonicPage... Repeat this process for all pages that contain this module file!
Once you have completed that step, make sure to import your pages in your app.module.ts
Let me provide you with an example to demonstrate how it is done! Let's say we have a class named testerClass. The page structure after using
ionic g page testerClass would look like
https://i.sstatic.net/gQ53G.png
Delete the tester-class.module.ts file
Step 2: AFTER deleting the module file, you need to navigate to tester-class.ts and
delete the annotation and import of IonicPage as shown in the image
https://i.sstatic.net/qw4zI.png
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NOTE!! Make sure to run the build commands as an admin/root user (if you are not already using a root account). In simple terms, search for cmd in the Windows search bar, right-click and select 'Open as administrator'
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