courtesy call
US /ˈkɜːr.tə.si ˌkɑːl/
UK /ˈkɜːr.tə.si ˌkɑːl/

1.
a visit or telephone call made as a matter of politeness or goodwill, rather than for a specific purpose
:
•
The new ambassador paid a courtesy call on the president.
•
I just wanted to make a quick courtesy call to see how you're doing.