I've also waited for a couple of days but it says staking is not in progress.
Does anyone know what's the condition of making staking to work?

Current I have one peer connected:
"addr" : "85.214.20.252:20382",

getstakinginfo
{
    "enabled" : true,
    "staking" : false,
    "errors" : "",
    "currentblocksize" : 0,
    "currentblocktx" : 0,
    "pooledtx" : 0,
    "difficulty" : 65536.00000000,
    "search-interval" : 0,
    "weight" : 0,
    "netstakeweight" : 2770578247,
    "expectedtime" : 0
}

getmininginfo
{
    "blocks" : 16560,
    "currentblocksize" : 0,
    "currentblocktx" : 0,
    "difficulty" : {
        "proof-of-work" : 0.00070424,
        "proof-of-stake" : 65536.00000000,
        "search-interval" : 0
    },
    "blockvalue" : 0,
    "netmhashps" : 0.00015451,
    "netstakeweight" : 2770578247.31587172,
    "errors" : "",
    "pooledtx" : 0,
    "stakeweight" : {
        "minimum" : 0,
        "maximum" : 0,
        "combined" : 0
    },
    "stakeinterest" : 1000000,
    "testnet" : false
}

Min. stake age      168 hours
Max. stake age      Unlimited

Your stake weight is missing above, and netstakeweight is extremely high at the moment.