Coleman, 24, said on his social media account that he had unsuccessfully challenged an Athletics Integrity Unit finding that he missed a test on 9 December, 2019.
"And now this might result in me being suspended from other filing failures that occurred well over a year ago at this point," he added.
The American narrowly avoided a ban last year after three violations of anti-doping "whereabouts" rules across 2018 and 2019. Those offences were recorded on 6 June, 2018, 16 January, 2019 and 26 April, 2019.
However, Coleman successfully argued that the first missed case should have been backdated to the first day of the quarter - 1 April, 2018 - meaning the three failures fell just outside the required 12-month period.
Champion
Coleman surged to his first world title in Doha last September in 9.76 seconds and was among the favourites for the 2020 Olympic crown in Tokyo before the games were postponed until July 2021 due to the coronavirus pandemic.
With Coleman missing another meeting with testers, it means that his offences in January and April 2019 come into play.
Under World Anti-Doping Agency rules, any combination of three whereabouts failures - either missing a test or failing to file paperwork on time - within a 12-month period is deemed a doping offence punishable by a two-year suspension.
'Plot'
Coleman said the missed test in December had been a deliberate attempt by anti-doping officials to try and catch him out.
He said testers had visited when he was out shopping for Christmas presents at a nearby mall, something he said could be verified by his bank statements and receipts.
"I was more than ready and available for testing and if I had received a phone call I could've taken the drug test and carried on with my night," he added.
"I was only made aware of this attempted drug test the next day on December 10th, 2019 by the AIU when I got this failed attempt report out of nowhere. I was completely unaware anybody tried to test me the day before."
The report from the doping control officer posted by Coleman said the tester had arrived at his apartment and had failed to get a response after "multiple, loud knocks were made every 10 minutes" for an hour-long period.
"I've been contacted by phone literally every other time I've been tested," Coleman said. "Literally. (I don't know) why this time was different. He even said he couldn't hear the doorbell so why wouldn't you call me?"
Coleman said testers had reappeared two days later to carry out a test which he was present for.
"And I've been tested multiple times since, even during quarantine," Coleman added. "But of course, that doesn't matter, and the fact that I have never taken drugs doesn't matter either."
