Message type: E = Error
Message class:  REXCAJCH - Messages for Rent Adjustment Based on Swiss Law 
Message number: 026
Message text: One adjustment using relative and absolute methods is not allowed
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 REXCAJCH026, which states "One adjustment using relative and absolute methods is not allowed," typically occurs in the context of the SAP Real Estate Management (RE) module, particularly when dealing with adjustments in rental agreements or contracts.
Cause: This error arises when there is an attempt to perform an adjustment that mixes relative and absolute methods. In SAP Real Estate Management, adjustments can be made using two methods: Relative Method: Adjustments are made based on a percentage or a relative change from the current value. Absolute Method: Adjustments are made using a fixed amount or absolute value. The system does not allow a single adjustment to use both methods simultaneously, which leads to this error message.
Solution: To resolve this error, you should ensure that the adjustment you are trying to make uses only one method—either relative or absolute. Here are the steps you can take: Review the Adjustment Details: Check the adjustment entry you
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
REXCAJCH025 No external condition purpose found in adjustment rule &1 (modern.inv.)
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
REXCAJCH024 Setting "Option for Reduction" only possible when percentage entered
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
REXCAJCH027 Adjustment date for the reference interest rate is invalid
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
REXCAJCH028 Adjustment date for purchasing power protection is invalid
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.