One maybe on the phone comes up and tells (8)
I believe the answer is:
apprises
'one maybe on the phone' is the definition.
I can't tell whether this definition defines the answer.
'comes up and tells' is the wordplay.
'comes up' becomes 'rises' (rising is a kind of coming up).
'and' means one lot of letters go next to another.
'tells' becomes 'app' (I can't explain this - if you can you should believe this answer much more).
'rises' put after 'app' is 'APPRISES'.
Can you help me to learn more?
(Other definitions for apprises that I've seen before include "Informs" , "Gives someone information" , "Makes aware of" .)