Question on the Boxes ! (Crash Bandicoot N. Sane Trilogy)

Good time of day .
Gentlemen , I must say , I have a Pirate !
And now, the question :
If anybody had such problem - to collect all the boxes on the level , but the diamond did not appear (Just at the end of the spinning *Transparent* box 37\37) . but Diamond no =\
This is a bug ? or I do not understand something ?