Message type: E = Error
Message class:  FICODIAN_CUST - Messages for DIAN Magnetic Media Customizings 
Message number: 020
Message text: Enter a Valid From date that is before the Valid To date.
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
Unfortunately, there isn't any extra information in this error notice.
First, use our AnswerBot below to get a possible cause and solution (requires a premium subscription).
Also, review the in-depth Common Questions & Answers listed below; you could discover a solution there or be able to connect with others who have faced similar challenges.
You can also try searching the SAP support portal (support.sap.com) but you need a special user ID to access it. It is possible that an SAP support note exists that provides additional details about the mistake or even steps for fixing it.
The SAP error message FICODIAN_CUST020 indicates that there is an issue with the date range specified in a transaction or configuration related to customer data. Specifically, the error states that the "Valid From" date must be before the "Valid To" date. This is a common validation error in SAP systems when dealing with date ranges for records such as customer master data, pricing conditions, or other time-sensitive entries.
Cause: The error occurs when: The "Valid From" date is set to a date that is equal to or later than the "Valid To" date. There may be a data entry mistake where the dates were entered incorrectly. The system is trying to create or update a record with an invalid date range.
Solution: To resolve this error, you should: Check the Dates: Review the "Valid From" and "Valid To" dates that you have entered. Ensure that the "Valid From" date is earlier than the "Valid To" date. Correct the Entry:
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
FICODIAN_CUST019 Item Type is set as not relevant for repor format &1.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FICODIAN_CUST018 Enter Valid To value.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FICODIAN_CUST021 Enter Tax Number Type.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
FICODIAN_CUST022 Enter DIAN identification document.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
Click on this link to search all SAP messages.