A team involved in the visual effects on Oscar-winning Queen movie Bohemian Rhapsody have yet to be paid, according to media and entertainment union Bectu.

The union says it is handling cases worth £53,000 relating to the bankruptcy of Halo VFX, a London-based company that contributed to the film’s visual effects.

Bectu says the plight of the out-of-pocket workers highlights the need for a new industry code of practice to protect freelance workers when businesses go into administration.

Bectu’s assistant national secretary, Paul Evans, said: “I’ve never had a situation where individual Bectu members have been hit this badly. We can’t just shrug and move on.

“It’s not acceptable for VFX artists who have contributed to the success of multimillion-pound features to be the ones to carry risk and go unpaid for their hard work and talent.”

More generally, many risks, he said, were shouldered by freelance VFX workers, who were forced to accept long periods of unpaid overtime and antisocial hours, which eroded creativity and productivity. “It’s an industry that drives talented people out. The gender ratio is particularly male-heavy. Women often can’t stay in an industry that expects almost unlimited unpaid overtime as short notice.”

Bohemian Rhapsody, which has made almost a billion dollars at the global box office, won four awards on Sunday night: best actor for Rami Malek, best editing, best sound editing and best sound mixing.

• This article was amended on 27 February to reflect the fact the Halo VFX were not the only visual effects team working on the film.