ScriptOutputPropertyException: Script output property '{Project with id=15100 key=RSCPD}.{Issue with key RSCPD-1 and id 23996}.fields.customfield_11700.type' is undefined.

I installed YT today. I tries to import the project from Jira (8.15). With imports, I get a error below.
The error causing field does not occur in this ticket.
What exactly causes this error? I thought maybe the type, but this one is correctly defined, which can be seen in the same log.

02/01/23 17:25:15,830 DEBUG [@tzJobProcessor1] [ClientScriptRunner            ] [import_user_898259689@] RSCPD-1. Converting Jira field id=customfield_11700 name=CODE_REVIEW_SLA type=string

Import failed with error: Script output property '{Project with id=15100  key=RSCPD}.{Issue with key RSCPD-1 and id 23996}.fields.customfield_11700.type' is undefined
 jetbrains.youtrack.scripts.sandbox.EvaluationException: Script output property '{Project with id=15100  key=RSCPD}.{Issue with key RSCPD-1 and id 23996}.fields.customfield_11700.type' is undefined.
    at jetbrains.youtrack.scripts.internals.ExceptionsProcessingKt.withScriptingAndDBExceptionsProcessing$createException(ExceptionsProcessing.kt:28)
    at jetbrains.youtrack.scripts.internals.ExceptionsProcessingKt.withScriptingAndDBExceptionsProcessing$wrapSpecifically(ExceptionsProcessing.kt:61)
    at jetbrains.youtrack.scripts.internals.ExceptionsProcessingKt.withScriptingAndDBExceptionsProcessing(ExceptionsProcessing.kt:86)
    at jetbrains.youtrack.scripts.internals.ExceptionsProcessingKt.withScriptingAndDBExceptionsProcessing$default(ExceptionsProcessing.kt:17)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$doStart$3$1.invoke(ImportExtensions.kt:103)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$doStart$3$1.invoke(ImportExtensions.kt:102)
    at jetbrains.youtrack.scripts.internals.RunInContextKt.runInContext(RunInContext.kt:17)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$doStart$3.invoke(ImportExtensions.kt:102)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$doStart$3.invoke(ImportExtensions.kt:97)
    at jetbrains.youtrack.api.application.ThreadLocalToggleKt.runWith(ThreadLocalToggle.kt:27)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt.doStart(ImportExtensions.kt:97)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$start$1.invoke(ImportExtensions.kt:78)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$start$1.invoke(ImportExtensions.kt:77)
    at jetbrains.youtrack.scheduling.LocalQuartzExecutor$executeNonTransactional$1.invoke(LocalQuartzExecutor.kt:29)
    at jetbrains.youtrack.scheduling.LocalQuartzExecutor$executeNonTransactional$1.invoke(LocalQuartzExecutor.kt:28)
    at jetbrains.youtrack.core.jobProcessor.NamedThreadJobProcessorKt.withLocalName(NamedThreadJobProcessor.kt:37)
    at jetbrains.youtrack.scheduling.QuartzJobProcessorKt.asNonTxLocalRunnable$lambda-0(QuartzJobProcessor.kt:41)
    at jetbrains.exodus.core.execution.RunnableJob.execute(RunnableJob.java:41)
    at jetbrains.exodus.core.execution.Job.run(Job.java:135)
    at jetbrains.exodus.core.execution.ThreadJobProcessor.executeJob(ThreadJobProcessor.java:132)
    at jetbrains.exodus.core.execution.JobProcessorQueueAdapter.doExecuteJob(JobProcessorQueueAdapter.java:251)
    at jetbrains.exodus.core.execution.JobProcessorQueueAdapter.doJobs(JobProcessorQueueAdapter.java:161)
    at jetbrains.exodus.core.execution.ThreadJobProcessor.run(ThreadJobProcessor.java:110)
    at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: jetbrains.youtrack.scripts.persistent.ScriptOutputPropertyException: Script output property '{Project with id=15100  key=RSCPD}.{Issue with key RSCPD-1 and id 23996}.fields.customfield_11700.type' is undefined.
    at jetbrains.youtrack.scripts.persistent.ScriptableExtensionsKt.getRequiredProperty(ScriptableExtensions.kt:79)
    at jetbrains.youtrack.scripts.persistent.ScriptableExtensionsKt.requiredString(ScriptableExtensions.kt:152)
    at jetbrains.youtrack.imports.runtime.JsClientAdapter.transformIssueFieldValues$typeName(JsClientAdapter.kt:361)
    at jetbrains.youtrack.imports.runtime.JsClientAdapter.transformIssueFieldValues(JsClientAdapter.kt:392)
    at jetbrains.youtrack.imports.runtime.JsClientAdapter.transformIssueFieldValues(JsClientAdapter.kt:330)
    at jetbrains.youtrack.imports.runtime.JsClientAdapter.getIssues(JsClientAdapter.kt:688)
    at jdk.internal.reflect.GeneratedMethodAccessor827.invoke(Unknown Source)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at jetbrains.youtrack.imports.runtime.ClientInvocationsLoggingHandler.invoke(ClientInvocationsLoggingHandler.kt:19)
    at com.sun.proxy.$Proxy479.getIssues(Unknown Source)
    at jetbrains.youtrack.imports.runtime.ImportProcessingDocumentsKt$defineInitialClientRequest$1.invoke(ImportProcessingDocuments.kt:181)
    at jetbrains.youtrack.imports.runtime.ImportProcessingDocumentsKt$defineInitialClientRequest$1.invoke(ImportProcessingDocuments.kt:178)
    at jetbrains.youtrack.imports.runtime.ImportProcessingDocumentsKt.doProcessDocuments(ImportProcessingDocuments.kt:246)
    at jetbrains.youtrack.imports.runtime.ImportProcessingDocumentsKt.processDocumentsInProject(ImportProcessingDocuments.kt:149)
    at jetbrains.youtrack.imports.runtime.ImportProcedureKt.processProjects(ImportProcedure.kt:182)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt.doImport(ImportExtensions.kt:183)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt.access$doImport(ImportExtensions.kt:1)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$doStart$3$1$1.invoke(ImportExtensions.kt:113)
    at jetbrains.youtrack.imports.model.ImportExtensionsKt$doStart$3$1$1.invoke(ImportExtensions.kt:103)
    at jetbrains.youtrack.scripts.internals.ExceptionsProcessingKt.withScriptingAndDBExceptionsProcessing(ExceptionsProcessing.kt:77)
    ... 21 more