Since this explorer is database-free, it doesn't natively support address balances & transaction history. However, you can check it in :
https://explorer.nusacoin.org/address/nu1qea9uxneetmzjtxcudqgl77hnnh4j7vepe7j2qt{
"isvalid": true,
"address": "nu1qea9uxneetmzjtxcudqgl77hnnh4j7vepe7j2qt",
"scriptPubKey": "0014cf4bc34f395ec5259b1c6811ff7af39deb2f3321",
"isscript": false,
"iswitness": true,
"witness_version": 0,
"witness_program": "cf4bc34f395ec5259b1c6811ff7af39deb2f3321"
}