As I said above, IP whitelisting only makes sense if you have a static IP address. You do not have a static IP address. Therefore you must disable IP whitelisting. It's NOT enough to remove the IPs from the IP whitelist management, you have to disable the entire IP whitelisting feature.
Per my instructions above please go to Components, Admin Tools, Web Application Firewall, Configure WAF and set "Allow administrator access only to IPs in Whitelist" to No.
If you have already done that, please take a look at https://www.akeebabackup.com/documentation/troubleshooter/atwafissues.html for unblocking your IP address. Please follow all of the steps described on that page or click the big, red Unblock My IP button in Components, Admin Tools to have everything done for you except for renaming the main.php file.
If you get locked out again it's worth taking a look at the Components, Admin Tools, Web Application Firewall, Security Exceptions Log. Filter by your IP address. What is the Reason and Target URL of the records relating to your IP address? This will tell us why you are getting blocked.
Nicholas K. Dionysopoulos
Lead Developer and Director
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