Minimize loss function

i work on a complex model, the loss function used is SSIM_loss+ rmi_loss+texture_loss i want to minimize it but it is always in the range of 1.7 and 1 what should i do ? i use optimizer = optim.SGD(model.parameters(),, weight_decay=0.01)
scheduler = torch.optim.lr_scheduler.CyclicLR(optimizer, base_lr=0.001, max_lr=0.1, step_size_up=100, step_size_down=100, mode=‘triangular’, cycle_momentum=True, base_momentum=0.8, max_momentum=0.9, last_epoch=-1, verbose=False)