Foster wrote the original novelisation of the first Star Wars movie (published in 1976, months before the film came out), as well as the subsequent original novel Splinter of the Mind's Eye (1978). He also wrote the novelisations of the first three Alien movies, in 1979, 1986 and 1992. Disney, which inherited the payment obligations for all of these works, had ceased payments to Foster in 2015. The SFWA (Science Fiction Writers of America) guild attempted mediation to no response. In late 2020 the matter was publicised, leading to widespread condemnation of Disney and several other authors noting similar issues with payments on older work.
Foster does not go into details, but notes on his webpage.
"The irritating imbroglio with Disney, which you may have read about, is moving towards a mutually agreeable conclusion. A formal statement will be forthcoming."
Hopefully the matter will now be resolved and Disney will agree to uphold their contractual obligations moving forwards with both Foster and all other impacted authors.