As the legal marijuana industry continues to expand in the U.S., reaching 23 states and the District of Columbia, businesses and brands are increasingly turning to social media to attract cannabis consumers. But at least one social media company, the photo-sharing app Instagram, appears to be turning marijuana businesses away.

Instagram's war on weed has been an ongoing issue for the budding industry: hundreds of marijuana dispensaries, brands, and influencers have had their accounts deleted by the company in the past year. And while there are theories floating around about why this happens, Instagram has declined to clarify its policy.

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"Instagram has been incredibly valuable in giving a voice to the voiceless, and that's included cannabis patients and providers," Coral Reefer, a cannabis celebrity on social media, told ATTN:. "Posting our own use of cannabis has allowed patients and enthusiasts to take ownership of the 'stoner' image and see it overhauled in the public's eye."

Coral Reefer (alias) lost her 130,000 followers when Instagram deleted her account (for the second time this year) on Friday.

Besides posting photos of herself smoking weed—which is legal for medical purposes in California, where she lives—it is not immediately clear why her account was deleted. Prominent brands such as Leafly and the counterculture magazine High Times appear to be exempt from whatever policy is taking down smaller, cannabis-related Instagram accounts.

"It's a shame they aren't proud of the community that has grown on Instagram around cannabis. I hope that they can clarify their policy to reflect the interest of many of their users," Reefer added.

But it's not just individuals who are getting burned by Instagram's cannabis crackdown. For the marijuana industry in Oregon and Colorado, two states where marijuana is legal for medical and recreational purposes, account removals are increasingly common among dispensaries and cannabis brands.

"They wake up one morning to find the following they've been building for months has been destroyed and they'll never get much of an answer why," the Willamette Week reported. "[C]losures were 'explained' in an email, stating the accounts were flagged for terms of service or community guideline violations and suspended—effectively deleted, since the form offered to appeal the suspension has never been answered by Instagram."

Instagram's community guidelines includes this line:

"Offering sexual services, buying or selling illegal or prescription drugs (even if it's legal in your region), as well as promoting recreational drug use is also not allowed."

If the social media company considers smoking medical marijuana in a legal state as "promoting recreational drug use," then that might serve as one possible explanation for the cannabis-related account removals.

ATTN: reached out to Instagram in an effort to answer those questions, but a representative for the company could not be reached by the time of publication.