If your strap has a flush fitting with the watch, the strap bars need to be carefully guided through the strap and into the other side of the watch.  The strap needs to be tight up against the watch and hence the bar is what’s called an interference fit through it. Please don’t ever struggle with strap fitting, call us for advice or send the watch to us and we’ll take care of it for you for nothing more than the cost of the return postage.