What is the "know the word but incapable to associate the word"-issue called that occurs mostly among non-native English speakers? [duplicate]

It happens to native English speakers, too. I'd be surprised if it didn't also happen to people who speak your first language. If you want an informal idiom to describe this phenomenon (rather than a psychological or linguistic technical term), here is one:

When a native English speaker knows a word for something but for some reason is unable to remember it, they can say that

"it's on the tip of my tongue,"

where "it" refers to the word.

And the technical psychological word for this (which I didn't know — I found it by searching for "tip of the tongue") is

lethologica.

This word is rare enough that many dictionaries don't contain it, and even psychologists often call it the tip-of-the-tongue phenomenon. Lexico defines lethologica as:

the inability to remember a particular word or name.