Message type: E = Error
Message class:  CNV20305 - Messages for conversion packages in CO 
Message number: 080
Message text: *** Messages for hierarchies ***
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 CNV20305080 is related to issues encountered during the conversion of hierarchies in SAP systems, particularly during data migration or system upgrades. This error typically arises in the context of SAP's data migration tools, such as the SAP S/4HANA Migration Cockpit or other conversion tools.
Cause: The error message CNV20305080 indicates that there is a problem with the hierarchy data being processed. Common causes include: Inconsistent Hierarchy Data: The hierarchy data may have inconsistencies, such as missing parent-child relationships or duplicate entries. Invalid Hierarchy Structure: The structure of the hierarchy may not conform to the expected format or rules defined in the system. Data Integrity Issues: There may be issues with the integrity of the data being migrated, such as references to non-existent nodes or circular references.
Configuration Issues: Incorrect configuration settings in the migration tool or the target system can lead to this error.
Solution: To resolve the CNV20305080 error, you can take the
 Get instant SAP help. Sign up for our Free Essentials Plan.
Get instant SAP help. Sign up for our Free Essentials Plan. 
CNV20305064 For target CoAr &1, target number ranges &2 and &3 overlap.
What causes this issue?  Number ranges &V2& and &V3& for controlling area &V1& are defined as overlapping in table CNV_NRIV_N....
CNV20305063 ... with no.rg. &2 in area &3 ( documents from CoAr &4 ).
What causes this issue?  Documents from CoAr &V4& are converted so that they are stored in target CoAr &V1& in number range &V2&am...
CNV20305081 Set type of set &1 in set class &3 was set to 'S' for CoAr &2.
Self-Explanatory Message Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of...
CNV20305082 CostCtr group &1 of CoAr &2 was attached to group &3 of CoAr &4.
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.