Going from white to red and back again is a high change In pigmentation.
Looks like you might not be purging enough between color changes.
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Check under Filament → Multimatetial → pigment percentage, if using Prusa Slicer/Super Slicer. Adjust the number accordingly for each color.
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increase the size of the purge block.
Pigment Percentage should be adjusted from 0 to 1 based on the filament pigment. 0 = natural/clear. 1 = black. This should be taken into consideration for how much purging is necessary to clean out the nozzle during the wipe tower moves. example: Light to Dark = less purging, Dark to Light = more purging needed.