Perhaps your billable or actual costs reports are showing values similar to below.
Confirm that the Resource is an Active under Staff (if applicable). Navigation: Business>Staff or see: Staff for full details.
Confirm that the resource is an Active Resource and has been assigned a Classification within the Resource table. Navigation: Business>Settings>Cost Management>Resource
Confirm that that Classification is Active and populated with applicable rates in Pure Cost (cost) and Pricing Table (sell) Navigation: Business>Settings>Cost Management
While you are in the Pure Cost and Pricing Tables, confirm that the frequency is not "No Charge."
You may also need to also confirm that the Resource has been allocated a Classification at Task level. Navigation: Job>Job Management>Specific Job number> Specific Task. Click on the Change button to rectify. You will need to run this check if the job was created before the Resource was assigned a classification on setup (under staff) or at Resource level (item 2).
5. During Time Approval your authorised personnel has changed the Charge Rate to No Cost. No Cost allows the hours to be recorded against the job, but no costs added to Job Cost or Billable calculations.