Fuji San vs Fuji yama

Why Japanese society called Mt Fuji as Fuji San?
Instead of Fuji yama/Fuji hill.

In Japanese Mt Fuji is called •xŽmŽR which is pronounced as fujisan. However in other words the kanji ŽR is pronounced yama.

In Japanese due to the Chinese origin of its kanjis most kanji have at least two ways of pronunciation which are drastically different. One is �gJapanese style�h and the other one �gChinese style�h pronunciation, to explain it simply. �gChinese style�h however doesn�ft mean that it sounds like present day Chinese but as Japanese people heard it back in the day when they imported that kanji/word. Wikipedia explains it way better: https://en.m.wikipedia.org/wiki/Kanji#Kun'yomi_(native_reading) (see kunyomi and onyomi section)

Now when Japanese words were first imported into foreign languages some �gtranslation �g errors were made. So while fujisan is the correct Japanese pronounciation of its kanji the last kanji got changed to Yama , which is correct only if that last kanji would stay alone. Or aparently is an old poetic form of receding to fujisan as �gFuji no yama�h: https://en.m.wikipedia.org/wiki/Mount_Fuji

There is no difference in meaning between Yama and San, so not like hill and mountain as you seem to intend.

And I am pretty sure that Japanese people are now very used to foreigners saying fujiyama and will potentially even answer using �gFujiyama�h in order not to confuse you, but then as a matter of fact they are using the English name of the mountain.

Thanks so much For your prompt reply.
In Japan, I found a foreigner always help other Foreigner.