Search is not working in sp 2016 while everything seems to be ok

Hi @munmun poddar ,
The cause of the problem is more complicated, I can't reproduce it in my environment, I found some posts similar to yours for your reference:
https://social.technet.microsoft.com/Forums/en-US/149353e4-7df8-49ca-b85a-fafde049efff/event-id-2159-event-45-and-223
https://sharepoint.stackexchange.com/questions/230596/cannot-get-sharepoint-2016-search-working
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Hi @munmun poddar ,
Great to know that and thanks for sharing the update here.

By the way, since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others.". and according to the scenario introduced here: Answering your own questions on Microsoft Q&A, I would make a brief summary of this thread:

[Search is not working in sp 2016 while everything seems to be ok]

Issue Symptom:
Search is not working in our SP2016. We checked our Search Administration page and all components are in green tick. Crawl is also working as expected. We checked for one item that is crawled but still no results. On checking Event Viewer we found the below error:
Event 223 (Search) of severity 'Critical' occurred 3 more time(s) and was suppressed in the event log

Somewhere in ULS logs we found:
WcfSendRequest: RemoteAddress: 'http://idcdeba099-app1:32843/da9c1114d0a14d9f88559594588a078f/SearchService.svc' Channel: 'Microsoft.Office.Server.Search.Administration.ISearchServiceApplication' Action: 'http://tempuri.org/ISearchSiteAdministrationServiceApplication/GetSearchApplicationName' MessageId: 'urn:uuid:c0d2e0c3-b8da-4fb3-9b2c-3258e5de7241'

Current status:
Finally found that there was time synch issue between my app and wf server which caused this problem. We sycnhed the server time and it got resolved.
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I did all the steps mentioned in the posts. But Finally found that there was time synch issue between my app and wf server which caused this problem. We sycnhed the server time and it got resolved.