[Shadow_]

Code:

 CMD:sendinfo(playerid,params[])
{
    new admin[25],account[25],reason[128],details[128];

    if(sscanf(params, "s[25]s[25]s[128]s[128]",admin,account,reason,details)) return SendClientMessage(playerid, -1,  "/sendinfo <string> <string> <string> <string>");

    printf("%s | %s | %s | %s",admin,account,reason,details);
    return 1;
}

Worked fine for me?

Code:

 Testing | Testing | Tesing | TESTINGEVENLONGERTESTING

My discord if you want to discuss more "Shadow_#0001"

Edit: I also just tried the exact copy of your CMD and it worked fine. So maybe if you have an issues its likely with the rest of your command not this snippet you've put forward.