C programming - While loop and scanf

Could anyone advise why my scanf function only works once and it ends in a continuous loop.

#include <stdio.h>
#include <conio.h>

int main(void)
{
    int accno;
    float bbal, charge, rebate, limit, balance;

    printf("Enter account number (-1 to end):");
    scanf("%d", &accno);

    while (accno != -1) // User input phase
    {
        printf("Enter beginning balance:"); // User input phase
        scanf(" %.2f ", &bbal); // leave space after scanf(" 

        printf("Enter total charges:");
        scanf(" %.2f ", &charge);

        printf("Enter total rebates:");
        scanf(" %.2f ", &rebate);

        printf("Enter credit limit:");
        scanf(" %.2f ", &limit);

        balance = bbal - charge + rebate;

        // credit limit exceeded phase
        if (balance > limit)
        {
            printf("Account: %u", accno);
            printf("Credit limit: %.2f", limit);

            balance = bbal - charge + rebate;

            printf("Balance: %.2f", balance);
            printf("Credit limit exceeded!");
        }
        printf("Enter account number (-1 to end):");
        scanf("%d", &accno);
    }

    getch();
}

via Chebli Mohamed