Sometimes after you've completed a Bulk Price Change, a client's appointment may still be displaying the old price (and therefore a discount at sale).
If this happens, don't worry, you can wipe the sweat off your brow and calmly proceed by
1) Editing the service/session or product at 'POS' to reflect the price change as you go
When you're ready to finish the sale:
1i) Add the client to sale
1ii) Click on the service(s) applying the discount
1iii) In the right-side panel de-select the original service from the 'Service' drop down
1iv) Re-select the original service from the 'Service' drop down
1v) Click 'Save' to resolve the issue
The service will no longer have the discount applied.