query to flag ID/Customer discrepancies

I have a customer and transcation table in an access database that I need to do some exception reporting on. Every customer has a unique customerID (or should), which is one of the key fields. Therefore, in the tables, in theory, every customerID should have the same corresponding customerForename and customerSurname information.

There is also a table called transactions, and I wanted to identify any instances whereby a customerID has more than 1 customerForename and customerSurname linked to the customerID column, as these are discrepancies.

So in the example below, customerID 123456 has 2 different forename, surnames linked to the same unique customer ID, whereas the query would not flag 78910 as that cusomterID has the same forename/surname for all records in the table:

Customer ID – CustomerForename – CustomerSurname
123456 – David – Smith
123456 – David – Jones
78910 – David – Expert
78910 – David - Expert

In Excel you can use tools like Pivot tables, but there is hopefully a way to identify such anomalies in Access SQL. Any general guidance or pointers would be a great help.