If you are facing issue related to "EDI conversion errors" like below, the steps mentioned in the resolution may help you to overcome this error

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2019 Nov 07 17:33:30:502 GMT +0530 BW.BusinessConnect-Interior_Server Error [bw.logger] BW-EXT-LOG-100000  No biz agreement exists between   and CompanyB 
2019 Nov 07 17:33:30:502 GMT +0530 BW.BusinessConnect-Interior_Server Debug [bw.logger] BW-EXT-LOG-300002  No biz agreement exists between CompanyB and CompanyB
    at com.tibco.ax.tibedi.config.PartnerInfoHelperImpl.init(PartnerInfoHelperImpl.java:212)
    at com.tibco.ax.tibedi.config.PartnerInfoHelperImpl.<init>(PartnerInfoHelperImpl.java:124)
    at com.tibco.ax.tibedi.config.PartnerInfoHelper.<init>(PartnerInfoHelper.java:27)
    at com.tibco.ax.tibedi.config.PartnerInfoHelper.<init>(PartnerInfoHelper.java:31)
    at com.tibco.ax.tibedi.runtime.pf.inbound.BMHPreProcessor.convertDataToUTF8(BMHPreProcessor.java:418)
    at com.tibco.ax.tibedi.runtime.pf.inbound.BMHPreProcessor.executeTask(BMHPreProcessor.java:383)
    at com.tibco.ax.tibedi.runtime.pf.inbound.BMHPreProcessor.Start(BMHPreProcessor.java:91)
    at com.tibco.ax.tibedi.runtime.inbound.EDIBMHService.validateDocument(EDIBMHService.java:144)
    at com.tibco.ax.fw.runtime.inbound.impl.IBBMHService.preProcessMsg(IBBMHService.java:217)
    at com.tibco.ax.fw.runtime.impl.AbstractService.preProcessor(AbstractService.java:291)
    at sun.reflect.GeneratedMethodAccessor61.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.tibco.plugin.gateway.InvokeOperationActivity.sInvokeServiceOp(InvokeOperationActivity.java:246)
    at com.tibco.plugin.gateway.InvokeOperationActivity$OperationThread.run(InvokeOperationActivity.java:376)
    at com.tibco.pe.util.ThreadPool$ThreadPoolThread.run(Unknown Source)
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In the above usecase 'CompanyA' is the Trading Partner.

- First, the inbound document should have the "TP (trading partner) interchange id (sender)" and "Host Interchange id (receiver)" listed in the log.

 In the above use-case the inbound document is using the same value for the  TP interchange id and the Host Interchange receiver and not the Interchange qualifier of the host.

- Because of the data problem, you can see " No biz agreement exists between CompanyB and CompanyB" error in Interior Server log. Because both ids are pointing to TP only. 

NOTE:   The ids should point to Trading Partner as well as to host.

- Here is an example of a faulty EDIFACT document -> Please see below:

This '123456789' is Trading Partner interchange id and this 123456789 is also the Host interchange id. Instead of 123456789, it should be something like (987654321 extracted from host configuration)

UNB+UNOA:1+123456789:1:REVERSE ROUT+123456789:1:ROUTING ADDR+100128:1437+2+RECEIVER PSWD:AA+APPL REF+A+1+COMM AGREE ID+1'

If you change the inbound document like below, it will correct the issue as the document will contain both i.e "TP interchange id(sender)" and "Host Interchange id (receiver)".

UNB+UNOA:1+123456789:1:REVERSE ROUT+987654321:1:ROUTING ADDR+100128:1437+2+RECEIVER PSWD:AA+APPL REF+A+1+COMM AGREE ID+1'