Welll… I know nothing about your environment, I don’t know of anything about what you have tried to do to figure it out yourself… I don’t know if you upgraded/changed anything recently…
On the other hand I have a similar issue to this to which I attribute my mistakenly upgrading Elasticsearch beyond 7.10.2… which is the last supported version… maybe you made the same mistake as me? Hard to tell.
On a side note - there are a couple of post to check out here and here that give hints on how to post a question in the forum… 