Too late to "fix" this, 3 or 4 weeks ago when this probably first started appearing, there may have been a chance, but anything you do now will not solve anything before harvest maturity.
These problems are generally the result of stopping "grow" nutrients and switching to "bloom" nutrients far too early in the flowering cycle.
Cannabis still needs adequate nitrogen in the beginning of flowering.
However, your diary is too vague to confirm or deny this opinion.