Deleting issues, LexoRank Balancing and Issues in Epic do not render

Boris Link_8khsg8

We are encountering multiple errors in Jira 8.7 hosted on our server:

1. Can't delete issue

https://community.atlassian.com/t5/Jira-Software-questions/Cannot-delete-issue-LexoRank-Related/qaq-p/1057358

When I try to apply the proposed fix https://confluence.atlassian.com/jirakb/remove-duplicate-rank-fields-in-jira-server-779159223.html?_ga=2.194018477.163707424.1584962666-1047052085.1584704350

And run step one: I only get: 10005 in return, so there don't seem to be duplicate Rank fields.

2. Issues in epic do not render:
https://confluence.atlassian.com/jirakb/issue-screen-displays-error-rendering-greenhopper-epics-issue-web-panel-in-jira-server-779158857.html

When I run the proposed Select:

<span>SELECT</span> <span>*</span> <span>FROM</span> issuelink  il
<span>WHERE</span> il<span>.</span>LINKTYPE <span>=</span>
  <span>(</span> <span>SELECT</span> id <span>FROM</span> issuelinktype <span>WHERE</span> linkname <span>=</span> <span>'Epic-Story Link'</span><span>)</span> 
<span>AND</span>
<span>(</span>
  il<span>.</span>destination <span>IS</span> <span>NULL</span>
  <span>OR</span> il<span>.</span>SOURCE <span>IS</span> <span>NULL</span>
  <span>OR</span> <span>not</span> <span>exists</span> <span>(</span><span>SELECT</span> <span>null</span> <span>FROM</span> jiraissue ji <span>where</span> ji<span>.</span>id <span>=</span> il<span>.</span>destination<span>)</span> 
  <span>OR</span> <span>not</span> <span>exists</span> <span>(</span><span>SELECT</span> <span>null</span> <span>FROM</span> jiraissue ji <span>where</span> ji<span>.</span>id <span>=</span> il<span>.</span>source<span>)</span> 
<span>)</span><span>;</span>

No issues are found.

3. Balancing in LexoRankManagement doesn't even show up.

And the proposed fix: 

https://confluence.atlassian.com/jirakb/how-to-fix-duplicate-rank-values-for-a-rank-field-779159224.html

with PUT doesn't solve the issue and creates this output:

Expected to find one rank row, but found 0 rows

Any suggestions and if you need further details, please ask for it and I will provide them as best as I can.