google cloud platform – Document AI Custom Doc Splitter – Internal error encountered

I created a training set for custom document splitter with a total 3803 docs and 158 labels. I checked with documents quota and limits and all my docs and pages are within the limits. When I run the training I got this following error message
Internal error encountered.
{
“name”: “projects/945951207848/locations/us/operations/4890234249887707766”,
“done”: true,
“result”: “error”,
“response”: {},
“metadata”: {
“@type”: “type.googleapis.com/google.cloud.documentai.uiv1beta3.TrainProcessorVersionMetadata,
“commonMetadata”: {
“state”: “FAILED”,
“createTime”: “2023-10-11T10:41:01.258619Z”,
“updateTime”: “2023-10-11T16:41:45.453832Z”,
“resource”: “projects/945951207848/locations/us/processors/fd97f52566718e15/processorVersions/43dd9a2405017f3c”
},
“trainingDatasetValidation”: {},
“testDatasetValidation”: {}
},
“error”: {
“code”: 13,
“message”: “Internal error encountered.”,
“details”: []
}
}

I retrained it again, but I still get the same error.