If you're noticing that the plug in your smart trainer's power port feels loose and/or the trainer powers off if it's wiggled, the pin inside the power port likely needs to be adjusted.
In the center of the power port on the trainer is a pin that is split down the middle - there is a 1.5mm gap between the halves. With normal use and plugging in/unplugging the trainer, the two halves can get pinched together, which causes a loose connection for the plug.
If upon visual inspection there is no gap between the two halves of the pin, it's advisable to spread them apart gently, 1-2mm. This will create a more snug fit for the plug, and will ensure a more consistent connection between the plug and the trainer.