Can you explain what you mean by syntax of writing minutes in the SLA field?
Are you using the due-date /time-centric measurement.
The typical way of writing minutes is with 'm' but you need to use the time centric measurement to my knowledge.
If you could share some more context on this issue, I would be happy to help clarify.
I can see from yours it is requesting you write the whole minutes from the UI.
Can you try this?
Normal the expected configuration is as follows.
As you can see I am entering based on the example given and yours shows up as 4 hours 30 minutes so I will use exactly that.
If this doesn't help, then can you share the language you are using so I can test this?