You don't have permission to delete a version

[Martin Sun]

I have no permission to delete a release ( version ) , how can I deal with it? 

[Clifton Foster]

The answer is to start at the Project level and not the General Settings. Within your Project Settings, go to Fields. Click the little pencil in the upper right and search for you field. Change the Renderers from there to [Wiki Style Renderer].

This is explained more here, as stated by @Bhushan Nagaraj 
https://community.atlassian.com/t5/Jira-questions/Troubles-with-wiki-style-renderer-for-custom-field-text-field/qaq-p/265301#U1996578 

[Bhushan Nagaraj]

Hi Andrew,

There are no limits on how many custom fields can use wiki renderer.

I suspect it might be a configuration issue. Can you please try the solution provided at https://community.atlassian.com/t5/JIRA-questions/Troubles-with-wiki-style-renderer-for-custom-field-text-field/qaq-p/265301

Specifically, the field configuration your project is using.

Thanks

Bhushan