I put some code but in a part of the code says error, but i don't know what is the error (its for a online game if you wanted to ask)

type_event = ds_map_find_value(async_load,"type");

switch(type_event)

{

case network_type_data

buffer = ds_map_find_value(async_load,"buffer");

buffer_seek(buffer,buffer_seek_start,0);

Receive_packet_client_sc(buffer);

break;

}

do you find something wrong on this code?, especially in the part

buffer = ds_map_find_value(async_load,"buffer");

that is the part with the error, how do i fix it?, tell me please