Send data file from client UDP ipv6 to the server - c

Question

I try to send a file data size of around 100MB from the client to the server in UDP ipv6.
the server I think it works well but the client I cannot figure out why I cannot send the file.
When I try to "sendto" I got the message: perror("[-]Error in sending the file. in UDP CLIENT")"
here is my code:
void client() {
int sockfd;
char buffer[65536];
struct sockaddr_in servaddr;
// Creating socket file descriptor
if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
perror("socket creation failed");
exit(EXIT_FAILURE);
}
memset(&servaddr, 0, sizeof(servaddr));
// Filling server information
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(P);
servaddr.sin_addr.s_addr = INADDR_ANY;
int n, len;
FILE *fp = fopen("data.txt","r");
char data[SIZE] = {0};
while (fgets(data, SIZE, fp) != NULL) {
if (sendto(sockfd, data, sizeof(data),
MSG_CONFIRM, (const struct sockaddr *) &servaddr,
sizeof(servaddr)) == -1) {
perror("[-]Error in sending file. in UDP CLIENT");
exit(1);
}
bzero(data, SIZE);
}
printf("Hello message sent.\n");
n = recvfrom(sockfd, (char *) buffer, 65536,
MSG_WAITALL, (struct sockaddr *) &servaddr,
&len);
buffer[n] = '\0';
printf("Server : %s\n", buffer);
close(sockfd);
}