Message type: E = Error
Message class:  /IWBEP/CM_MGW_RT -  
Message number: 133
Message text: Association set '&1' references to disabled entity set '&2'
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 /IWBEP/CM_MGW_RT133 indicates that there is an issue with an association in your OData service. Specifically, it states that the association set references an entity set that has been disabled. This can occur in the context of SAP Gateway and OData services when there are issues with the configuration of the service or the underlying data model.
Cause: Disabled Entity Set: The entity set referenced in the association is disabled in the service definition. This can happen if the entity set is not included in the service or if it has been explicitly marked as disabled. Model
Configuration Issues: There may be issues in the data model configuration, such as incorrect associations or references. Service Registration: The OData service may not be properly registered or activated in the SAP Gateway. Authorization Issues: There may be authorization issues preventing access to the entity set.
Solution: Check Entity Set Status: Go to the SAP Gateway Service Builder
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
/IWBEP/CM_MGW_RT132 Association set '&1' references to disabled association '&2'
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
/IWBEP/CM_MGW_RT131 Action '&1' inconsistent
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
/IWBEP/CM_MGW_RT134 Navigation property '&1' references to disabled association '&2'
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
/IWBEP/CM_MGW_RT135 Complex type property '&1' references to disabled complex type '&2'
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.