Instagram shows you Ads relevant to your search history , liked pages , liked posts, in short, Instagram shows you Ads relevant to your interest. so if you want to hide posts relevant to your interest then its very easy... just follow my instructions.
open your Instagram profile and go to settings like this
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select option "Ads" like this
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now turn Off option "Opt out of interest based ads" like this
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in this way interest based ads will be closed.
thankyou....