Thank you for asking. Just to make sure, are you referring to the Samsung Galaxy A50?
I'm sorry to tell you, but the A50 is missing support for Depth API in ARcore, which this currently depends on. Depth API is needed to gauge the distance from the device to the surface that the camera is pointed at.
You can see a list of the supported features based on device here:
ARCore supported devices | Google for Developers
Any device that supports Depth API should work, but I can't guarantee it, without testing the specific devices.
I will address this in the future by seeing if I can find an alternate approach or if I will need to add an error message, indicating that the device is not supported.