Employees not wanting to work different hours

I’m a manager in an organization which is struggling due to the impact of the pandemic. As part of our increased offer to our clients, we have been asked to extend our hours of coverage. This means my team will have to take turns working a slightly later shift (10am-6pm) as opposed to their preferred 8am-4pm shift. This is the last in a series of adjustments they have had to make, all the while dealing with vacancies in the team meaning their workloads are currently high.
C: Employees have said they do not want to work 10-6 shift
T: I have failed as a manager
F: Despair
A: Cry, be upset, not able to sleep, unable to focus, spinning in negative thoughts
R: Don’t get closer to a resolution

I’m struggling with my intentional model, given that my result cannot be anything to do with other people doing what I want – I want them to agree to work the later shifts but I know I cannot control it.

C: Employees have said they do not want to work 10-6 shift
T: This is not a reflection on my capabilities as a manager (? I don’t actually believe this, I do think I’m responsible)
F: Calm
A: Think of other ways that may help me achieve my goal of getting coverage till 6pm (?)
R: Take action to try and achieve goal (?)

I’d love some feedback on my models!