Blockstack-cli testnet issue

Core Blockchain Command Line (CLI)
#1

I am trying to use blockstack-cli to generate address then check balance and so on.However I faced an issue for getting the balance as below :
blockstack-cli -t make_keychain
{
“mnemonic”: “grant leisure camp jewel season tragic stadium green nurse air tag client”,
“ownerKeyInfo”: {
“privateKey”: “97387a8fe548cead768e654d610a9d6f60021f4fa0cf6677262ab17d2e7b719e01”,
“version”: “v0.10-current”,
“index”: 0,
“idAddress”: “ID-mmxHiEYB76nQWb8rFx1SSXDcG2EehEtVqG”
},
“paymentKeyInfo”: {
“privateKey”: “0958d10b97fafc5643f5a569037dc8e2b5bf6e542f09eadfde6e8146ddaae4cb01”,
“address”: {
“BTC”: “mjvvcqbXR3Gh8c4cziUWGrNs5CY2jn5dLd”,
“STACKS”: “STR6J5J9DHBA4E563SM35HX39KTFE382ZTK3QY5A”
},
“index”: 0
}
}

blockstack-cli -t balance STR6J5J9DHBA4E563SM35HX39KTFE382ZTK3QY5A
FetchError: invalid json response body at http://testnet.blockstack.org:18332/ reason: Unexpected token < in JSON at position 0
    at /root/blockstack/cli-blockstack/node_modules/node-fetch/lib/index.js:254:32
    at processTicksAndRejections (internal/process/task_queues.js:85:5)
invalid json response body at http://testnet.blockstack.org:18332/ reason: Unexpected token < in JSON at position 0
#2

Sorry about that; should be fixed now. The new firewall we installed on the public testnet was being too aggressive about which Bitcoin RPC commands it was filtering out.