3037484 - In Plan Customer Projects app, error "Sorry, the plan data couldn't be saved due to errors." when setting Stage "In Execution"

In app Plan Customer Projects, when trying to set the Stage to "In Execution" for a project and the error "Sorry, the plan data couldn't be saved due to errors." is triggered.

SAP S/4HANA Cloud Public Edition

1. Open app Plan Customer Projects.
2. Open a project.
3. Set Stage to "In Execution".
4. Click Save.
5. Receive error "Sorry, the plan data couldn't be saved due to errors.".

One possible cause is missing currency exchange rates.

Maintain the currency exchange rates in app  "Currency Exchange Rates" for currencies and dates relevant to the project for rate type P (Cost Planning). As detailed in SAP Help Calculate Cost and Revenue:

Calculation of planned cost is based on exchange rate type P (standard translation for cost planning), and the exchange rate defined at the beginning of each calendar year is applied across corresponding months.

SAP Help Calculate Cost and Revenue

FINS_ACDOC_PLANNING015, FINS_ACDOC_PLANNING 015, LT_ACDOCP_DATA_EXTENDED, SG105, SG 105,  2979593, currency exchange rates, dates, currency, exchange, rate, Plan Customer Projects, In Execution , KBA , CA-CPD-SS , S/4HANA Public Cloud – Professional Service Projects , Problem