How about a brief discussion of the words “detail” and “details”
From the common phrase point of view, let’s look at some examples.
“Please describe the issue in more detail”.
“After further research, here are additional details on the problem.”
“Let us discuss the issue in more detail.”
Please look at these phrases, and get used to the “sound” of these phrases.
Please AVOID –
“Please describe the issue in more details” AND
“Let us discuss the issue in more details.”
The recommended use is illustrated in thse examples. The rules are hard to describe. My suggestion – just memorize the phrases themselves. Usage here only comprises a few different ways to use the word. Just memorize the PHRASE and don’t worry about the technicality of the rule.