Chrissy Teigen Rips Michael Costello, He Insists He's Telling the Truth

Chrissy Teigen says she has "no idea what the f*** Michael Costello is doing" when it comes to faking an alleged DM convo between them ... and she's doubling down, insisting he's lying.

Chrissy unloaded on the 'Project Runway' star Friday ... accusing him of fabricating the screenshots he released to the public to make it look like she had privately bullied him online.

CT says she actually thought things were cool between her and Michael until he suddenly accused her last week of mounting a yearslong campaign to get him blacklisted from the fashion industry over an alleged racist comment he made on social media.

Chrissy says she's "never conspired with anyone to harm his career" and claims they were being friendly online until he recently attacked, and claimed she nearly drove him to suicide.

As you know ... Michael posted what he says are direct Instagram messages from Chrissy calling him racist and threatening his career back in 2014 ... but she says those are all BS, and the proof is in the details of the purported DMs.

For instance, Chrissy says the camera icon for the video chat function in the upper right corner is the smoking gun -- video chats weren't available on IG until 2018 and she also points out the convo's color formatting appears to be from the app's 2020 update. In other words, she's saying there's no way the DMs are from 2014 ... so, the whole convo is fake.

As we reported ... John Legend came to his wife's defense earlier Friday, accusing Michael of faking the DMs just so he could insert himself in Chrissy's bullying controversy.

Chrissy also announced Friday she's stepping away from Safely, the self-care and home cleaning line she launched 3 months ago with Kris Jenner, to take time to focus on herself and be with her family.