Hi I'm just trying to get transactions for the address and getting this error from time to time (few times I got successfull response)

request:

 curl -X 'GET' 'https://toncenter.com/api/v2/getTransactions?address=EQBnvfmXYL_z7n4WriIEVrBNKVQBolTD5bx-syCe5B5EtqOy' -H 'accept: application/json'

error:

{"ok":false,"error":"LITE_SERVER_UNKNOWN: cannot compute block with specified transaction: lt not in db","code":500}

1. Why I'm getting this error periodically?
2. Do I need in my own Lite node to avoid this error? What is the reason to use own Lite node?

Thanks.