The /ŋ/ sound is spelled with <ng>. The /ʧ/ sound is spelled with <ch> or <tch>.
This is a contrast between a voiced velar nasal continuant and a voiceless alveolar affricate, only occurring in syllable-final position or in syllable-closing clusters. It is not a problem.
clung clutch dung Dutch hang hatch hanging hatching hanged hatched hung hutch king kitsch pang patch ping pitch pinging pitching pinged pitched rang ratch Reading Redditch ring rich ringer richer sting stitch stinging stitching sung such swing switch swinging switching tongue touch wing which wing witch winging witching