This issue is somewhat similar to a previous bug that was later fixed, in which the game would cease to function after a rendevous with a crewed spacecraft. Except in this scenario, the astronaut in other craft is booted out and can't be taken over again.
Steps are as followed last time:
1. Launch a spacecraft beyond 10km from the crewed spacecraft in question.
2. Rendevous with a crewed spacecraft (whether it's grounded or in orbit)
3. Within the 10km vicinity, the bug will occur.
Below I will put a link to a video demonstrating this.
https://youtu.be/3YWzzWOuGQE