Why is App/Input Page not loading after migration from addon builder 4.1.0?

[dmungara]

My published addon was build using addon builder 3.0.1. I updated the addon app by exporting it from Addon builder version 4.1.0 recently.
I am facing issue when we install the addon in fresh system. When I open the input page it gives 500 error and shows page like one attached with this message. Following are the exception from the splunkd.log:

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06-26-2022 13:36:02.878 +0000 ERROR AdminManagerExternal - Stack trace from python handler:\nTraceback (most recent call last):\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunktaucclib/rest_handler/handler.py", line 124, in wrapper\n for name, data, acl in meth(self, *args, **kwargs):\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunktaucclib/rest_handler/handler.py", line 179, in all\n **query\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunklib/binding.py", line 290, in wrapper\n return request_fun(self, *args, **kwargs)\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunklib/binding.py", line 71, in new_f\n val = f(*args, **kwargs)\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunklib/binding.py", line 686, in get\n response = self.http.get(path, all_headers, **query)\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunklib/binding.py", line 1199, in get\n return self.request(url, { 'method': "GET", 'headers': headers })\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunklib/binding.py", line 1262, in request\n raise HTTPError(response)\nsplunklib.binding.HTTPError: HTTP 404 Not Found -- b'{"messages":[{"type":"ERROR","text":"Not Found"}]}'\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n File "/opt/splunk/lib/python3.7/site-packages/splunk/admin.py", line 113, in init_persistent\n hand.execute(info)\n File "/opt/splunk/lib/python3.7/site-packages/splunk/admin.py", line 636, in execute\n if self.requestedAction == ACTION_LIST: self.handleList(confInfo)\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunk_aoblib/rest_migration.py", line 39, in handleList\n AdminExternalHandler.handleList(self, confInfo)\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunktaucclib/rest_handler/admin_external.py", line 63, in wrapper\n for entity in result:\n File "/opt/splunk/etc/apps/<APP_NAME>/bin/<APP_NAME>/aob_py3/splunktaucclib/rest_handler/handler.py", line 129, in wrapper\n raise RestError(exc.status, str(exc))\nsplunktaucclib.rest_handler.error.RestError: REST Error [404]: Not Found -- HTTP 404 Not Found -- b'{"messages":[{"type":"ERROR","text":"Not Found"}]}'\n
06-26-2022 13:36:02.878 +0000 ERROR AdminManagerExternal - Unexpected error "<class 'splunktaucclib.rest_handler.error.RestError'>" from python handler: "REST Error [404]: Not Found -- HTTP 404 Not Found -- b'{"messages":[{"type":"ERROR","text":"Not Found"}]}'". See splunkd.log for more details.

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This behavior is not reproducing in case we upgrade the addon from previous version.
Please help me resolve this.