Can't make migration to new version backendless: java.lang.NullPointerException

Hello! I have some problems with app migration (from 3.0 to latest).
New app for new version: ID 8392897F-5346-215F-FF0E-66F93B59B500

My application data (table schemes etc) are not uploaded. After clicking on the “Import” button, a window appears that the unzipping process is in progress and nothing else.

I have log from e-mail with error:java.lang.NullPointerException
1 12:37:29 IMPORT_DATA Importing Started.
2 12:37:29 IMPORT_DATA Preparing files to import
3 12:37:29 IMPORT_DATA Creating temporary tables
4 12:37:29 IMPORT_DATA Creating user’s tables
5 12:37:29 IMPORT_DATA Checking for existing views with the same names as in imported tables
6 12:37:29 IMPORT_DATA Checking denied, duplicate and dataSize for columns.
7 12:37:29 IMPORT_DATA Preparing Users table: initializing columns.
8 12:37:29 IMPORT_DATA Import of tables failed: null
9 12:37:29 IMPORT_DATA Importing failed. Exception:java.lang.NullPointerException
10
11 com.backendless.management.impex.manager.imports.data.CommonDatabaseUtils.ensureDataSize(CommonDatabaseUtils.java:71)
12 com.backendless.management.impex.manager.imports.data.ImportDataManager.initColumn(ImportDataManager.java:841)
13 com.backendless.management.impex.manager.imports.data.ImportDataManager.initColumns(ImportDataManager.java:812)
14 com.backendless.management.impex.manager.imports.data.ImportDataManager.initTables(ImportDataManager.java:759)
15 com.backendless.tasks.impex.ImportDataTask.doExecute(ImportDataTask.java:225)
16 com.backendless.tasks.impex.ImportDataTask.executeImpl(ImportDataTask.java:155)
17 com.backendless.tasks.impex.AbstractImportTask.execute(AbstractImportTask.java:71)
18 com.backendless.taskman.Task.run(Task.java:108)
19 com.backendless.taskman.TimeoutFixedThreadPoolExecutor.executeTaskWithTracker(TimeoutFixedThreadPoolExecutor.java:91)
20 com.backendless.taskman.TimeoutFixedThreadPoolExecutor.lambda$invoke$0(TimeoutFixedThreadPoolExecutor.java:39)
21 java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
22 java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
23 java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
24 java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
25 java.base/java.lang.Thread.run(Thread.java:829)

Please help!

Hello @Demchog_Expansion

Welcome to the community and thanks for trying Backendless out!

Could you please clarify the steps to reproduce the problem by describing points what did you do, like: 1) get the archive from… 2) create a new app… 3)…

Regards, Vlad

In addition, the 3.x version has reached its EOL (end of life) and is no longer supported. We still maintain the cluster where the applications are hosted, but we no longer make any changes in that version nor fix any bugs. For assistance with migration please contact sales@backendless.com to discuss your options

  1. open app ID 99FA5B16-7426-9BED-FFE9-5322C4CA9B00
  2. press the button “Copyyour app to 5.x”
  3. get the archive from backendless to my e-mai
  4. create a new app ID 8392897F-5346-215F-FF0E-66F93B59B500
  5. go to Manage, then Import
  6. Click the ‘Browse’ link for the “Backendless 3.x app archive” option and select the Data zip file.

and have error

nobody answer to me
I wrote twice

Migration out of 3.x is no longer supported by the product. The current version is 6.x. We might be able to assist you on a consulting basis, to get more details, please contact sales@backendless.com and reference the URL for this topic.

Regards,
Mark

I wrote the message to this e-mail.
please answer to me

Please, answer me to my e-mail.
I wait over 24 hours.
I have short time for the migration app