problem with import data

[Karim Belhadj]

hello team 

i try to import data to my instance from database h2 witch i configured it with MYSQL but after configuration when i try to import data one error appear i do not understand the problem :

This is my log.

2019-04-29 10:57:16,571 JiraImportTaskExecutionThread-1 ERROR anonymous 657x39x1 15g89vv 0:0:0:0:0:0:0:1 /secure/SetupImport.jspa [c.a.j.bc.dataimport.DefaultDataImportService] Error parsing export file: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.
org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at org.apache.xerces.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at com.atlassian.security.xml.RestrictedXMLReader.parse(RestrictedXMLReader.java:103)
at com.atlassian.jira.bc.dataimport.DefaultDataImportService.parseXmlAndValidateBackupData(DefaultDataImportService.java:390)
at com.atlassian.jira.bc.dataimport.DefaultDataImportService.doImport(DefaultDataImportService.java:290)
at com.atlassian.jira.web.action.setup.DataImportAsyncCommand.unsafeCall(DataImportAsyncCommand.java:82)
at com.atlassian.jira.web.action.setup.DataImportAsyncCommand.call(DataImportAsyncCommand.java:64)
at com.atlassian.jira.web.action.setup.DataImportAsyncCommand.call(DataImportAsyncCommand.java:30)
at com.atlassian.jira.task.ImportTaskManagerImpl$TaskCallableDecorator.call(ImportTaskManagerImpl.java:157)
at com.atlassian.jira.task.ImportTaskManagerImpl$TaskCallableDecorator.call(ImportTaskManagerImpl.java:133)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

I need help please 

Regards