Step 1.
Arcgis online does not have my esri link

Step 2.

Step 3.

Step 4.

Step 5.
must use incognito window login my esri.

Step 6.

Step 7.

Step 8.
my old arcgis online(hppolice.maps.arcgis.com) user name is : hppolice
new arcgis online (huntingtonpark.maps.arcgis.com) user name is : hppolice1 ( can not be same as old one )
the hppolice did connect to my esri, but hppolice1 did not connect to my esri.
leave it as is
here is how you add new user, give admin

Step 9.
how to add new user as admin
you must select a user, then manage user type popup,
without select a user, you can not change user type to admin

Step 10.

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