Can't Backup data - java.io.IOException: Illegal UTF-8: 0xFFFFFFB1

[2018-06-01 13:25:46] Log4jLoggerAdapter WARN  Exception in backup
org.apache.jena.atlas.RuntimeIOException: java.io.IOException: Illegal UTF-8: 0xFFFFFFB1
        at org.apache.jena.atlas.io.IO.exception(IO.java:233)
        at org.apache.jena.atlas.io.BlockUTF8.exception(BlockUTF8.java:275)
        at org.apache.jena.atlas.io.BlockUTF8.toCharsBuffer(BlockUTF8.java:150)
        at org.apache.jena.atlas.io.BlockUTF8.toChars(BlockUTF8.java:73)
        at org.apache.jena.atlas.io.BlockUTF8.toString(BlockUTF8.java:95)
        at org.apache.jena.tdb.store.nodetable.NodecSSE.decode(NodecSSE.java:101)
        at org.apache.jena.tdb.lib.NodeLib.decode(NodeLib.java:105)
        at org.apache.jena.tdb.lib.NodeLib.fetchDecode(NodeLib.java:81)
        at org.apache.jena.tdb.store.nodetable.NodeTableNative.readNodeFromTable(NodeTableNative.java:186)
        at org.apache.jena.tdb.store.nodetable.NodeTableNative._retrieveNodeByNodeId(NodeTableNative.java:111)
        at org.apache.jena.tdb.store.nodetable.NodeTableNative.getNodeForNodeId(NodeTableNative.java:70)
        at org.apache.jena.tdb.store.nodetable.NodeTableCache._retrieveNodeByNodeId(NodeTableCache.java:128)
        at org.apache.jena.tdb.store.nodetable.NodeTableCache.getNodeForNodeId(NodeTableCache.java:82)
        at org.apache.jena.tdb.store.nodetable.NodeTableWrapper.getNodeForNodeId(NodeTableWrapper.java:50)
        at org.apache.jena.tdb.store.nodetable.NodeTableInline.getNodeForNodeId(NodeTableInline.java:67)
        at org.apache.jena.tdb.lib.TupleLib.triple(TupleLib.java:107)
        at org.apache.jena.tdb.lib.TupleLib.triple(TupleLib.java:84)
        at org.apache.jena.tdb.lib.TupleLib.lambda$convertToTriples$2(TupleLib.java:54)
        at org.apache.jena.atlas.iterator.Iter$2.next(Iter.java:270)
        at org.apache.jena.atlas.iterator.Iter$2.next(Iter.java:270)
        at org.apache.jena.atlas.iterator.Iter.next(Iter.java:891)
        at org.apache.jena.riot.system.StreamOps.sendQuadsToStream(StreamOps.java:140)
        at org.apache.jena.riot.writer.NQuadsWriter.write$(NQuadsWriter.java:62)
        at org.apache.jena.riot.writer.NQuadsWriter.write(NQuadsWriter.java:45)
        at org.apache.jena.riot.writer.NQuadsWriter.write(NQuadsWriter.java:91)
        at org.apache.jena.riot.RDFWriter.write$(RDFWriter.java:208)
        at org.apache.jena.riot.RDFWriter.output(RDFWriter.java:165)
        at org.apache.jena.riot.RDFWriter.output(RDFWriter.java:112)
        at org.apache.jena.riot.RDFWriterBuilder.output(RDFWriterBuilder.java:149)
        at org.apache.jena.riot.RDFDataMgr.write$(RDFDataMgr.java:1269)
        at org.apache.jena.riot.RDFDataMgr.write(RDFDataMgr.java:1162)
        at org.apache.jena.riot.RDFDataMgr.write(RDFDataMgr.java:1153)
        at org.apache.jena.fuseki.mgt.Backup.backup(Backup.java:115)
        at org.apache.jena.fuseki.mgt.Backup.backup(Backup.java:75)
        at org.apache.jena.fuseki.mgt.ActionBackup$BackupTask.run(ActionBackup.java:58)
        at org.apache.jena.fuseki.async.AsyncPool.lambda$submit$0(AsyncPool.java:55)
        at org.apache.jena.fuseki.async.AsyncTask.call(AsyncTask.java:100)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
Caused by: java.io.IOException: Illegal UTF-8: 0xFFFFFFB1
        ... 40 more
[2018-06-01 13:25:46] Log4jLoggerAdapter INFO  Backup(/fuseki/backups/PDE_PROD_2018-06-01_13-24-00):2