Error during uploading to IPFS

The following error occurred while uploading using infura IPFS add api. Until recently, I used it without any particular error, but suddenly an error occurs frequently today. can i know the cause?

captured error is below.

[14.02.2022 09:10.47.384] [LOG] Error: rpc error: code = Unavailable desc = transport is closing
at IncomingMessage. (/work/NFTPlatform/NFTServer/node_modules/ipfs-api/src/utils/send-request.js:68:38)
at IncomingMessage.emit (events.js:387:35)
at endReadableNT (internal/streams/readable.js:1317:12)
at processTicksAndRejections(internal/process/task_queues.js:82:21)

@kim.sehyoung do you still encounter such errors?
if so, could you please share a curl that you are using? Thanks