How does Phase id in Phases get a value? Is it an auto-entered serial number?
If so, that one field unique identifies each record in Phases. IF not, you should define an additional field, set up as an auto-entered serial number, as the primary key for this table. Assuming Phase id is a unique identifier for now (you can use the new serial number field if it's not), set up this relationship:
Phases::Phase id = Time Punches::Phase id
Client id and Project id should be removed from the Time Punches table as they are not needed.
Then you can define a calculation field as Sum ( TIme Punches::Total ) to compute the total hours and Sum ( Time Punches::Cost ) as the total cost. In each case, the total will be of all the time punches records linked to the current Phases record by Phase ID.
Instead of calculation fields defined in phases, you can define two summary fields in Time Punches, one as the total of Total and one as the Total of Cost. Placing these summary fields on a Phases layout or referring to them in a calculation defined in Phases will also return the total hours and cost for that phase.