How to use Accept() for multiple connections - c

Question

I'm trying to send http response to the browser at my code (I use virtual machine of linux), when I debug my code I can tell that after one request and response, the accpet() function doesn't wait and continue the procedure even if I did close the socket-fd.
Does anyone have any idea why is this happening?
Here is my code:
while(1){ // infinite loop for requests
if (( user_socket = accept(fsockfd, (struct sockaddr *)&serv_addrf, // wait for a request from customer and accept new socket
(socklen_t*)&addrlenf))<0)
{
perror("accept");
exit(EXIT_FAILURE);
}
while(flag_rec!=1){
if(recv(user_socket, customer_reply , BUFSIZE , 0) < 0) // get the request from customer
{
puts("recv failed my man"); // in case of failing
}
for(int i=0; i<BUFSIZE;i++){
if(customer_reply[i]=='\r'&&customer_reply[i+1]=='\n'&&customer_reply[i+2]=='\r'&&customer_reply[i+3]=='\n'){ //checking if there is \r\n\r\n
customer_reply[i+4]='\0';
customer_reply_size=i+4;
flag_rec=1; // it means we received the full http request
break;
}
}
}
flag_rec=0;
if(send(serv_socket,customer_reply,customer_reply_size,0)<0){ // sending the http request to the servers
puts("send failed"); // in case of failing
}
while(flag_rec!=1){
if(recv(serv_socket,server_reply,BUFSIZE,0)<0){ // get the answer message from the servers
puts("recv failed mann"); // in case of failing
}
for(int i=0; i<BUFSIZE;i++){
if(server_reply[i]=='\r'&&server_reply[i+1]=='\n'&&server_reply[i+2]=='\r'&&server_reply[i+3]=='\n'&&server_reply[i+4]=='\0'){ //checking if there is \r\n\r\n
server_reply[i+4]='\0';
server_reply_size=i+4;
flag_rec=1; // it means we received the full http request
break;
}
}
}
flag_rec=0;
if(send(user_socket,server_reply,server_reply_size,0)<0){
puts("send failed"); // in case of failing
}
close(user_socket); // closing the socket after the response
}