Coronation Street stars Jack P. Shepherd and Colson Smith told Rochelle Humes and Phillip Schofield on This Morning that ITV soap icon William Roache doesn't know their names.
Jack, who plays stalwart David Platt, said: "I've been in the show 23 years and the other day, I'm in work walking down the corridor and Bill Roache, Ken Barlow, came in and he's come in with his little leather bag. I go, 'You alright, Bill?' and he goes, 'Morning, David.'"
The actor joked that the moment left him feeling "small" as Rochelle exclaimed: "Oh no!"
Phillip interjected: "He's just called you your character name."
"But 23 years he's known me and I thought, 'Really? Is that where we are.' But I'm not going to correct him."
"It's a hard thing to get your head around, obviously you know him personally...," Rochelle continued.
"Well, I thought I did!" Jack joked. "I'm not going to go, 'Oh it's Jack.' that's going to destroy his brain.
Jack's Coronation Street co-star revealed he wasn't the only one Bill refers to by the wrong name.
Colson added: "If it makes you feel better, he calls me Colin since day one."
The Coronation Street stars appeared on This Morning to discuss their Sofa Cinema Club podcast with fellow ITV soap star Ben Price, who plays Jack's on-screen brother Nick Tilsley.
Jack, Colson and Ben are taking their podcast on the road, performing at The Lowry in Salford, after their first live show last year.
Meanwhile, William Roache collected an OBE as the longest-serving soap star last year.
He was awarded the honour at Windsor Castle by King Charles after bagging a Guinness World Record for playing Ken Barlow for 62 years.
At the time, William said he was "immensely grateful" to Coronation Street, as "without the programme I wouldn't be in this position".
"I'm delighted to be receiving an OBE as it's such a wonderful honour. I can't tell you how proud I am," he continued.
"Coronation Street has given me so much in life and I absolutely love the programme and everyone who works on the show."