#N/A means that the data is "Not available." Possible reasons are 1. An error server in the formula. Check the correct value: "market.rtd". 2. An error in arguments. Check the provider, symbol, and the data field. 3. A bad ticker. Check the ticker at https://finance.yahoo.com/. 4. Data absent in a data source. For example, Open, DaysHigh, and DaysLow can be not available during non-trading hours.
The data are not being refreshed
Add formulas to monitor data status: rtd_LastUpdate, rtd_LastError, rtd_RefreshInterval. See the description in Application Fields.