I'm not new to Altium Designer; I have been actively using it for at least one year and I have a very weird problem.
I completed a huge PCB project about 2 months ago. Recently, I realized there was a small mistake in the schematic and I wanted to fixed it. I just swapped the two connections of a component (ie. swapped the TX/RX connection). After I had made the change in schematic and hadsaved it, I moved to the PCB editor (Layout) to do the small trace swapping operation.
But interestingly, the components that were affected from the fixing in in the schematic started to act weird: I can't move those four components where I want, but the others are all good. When I drag and release a component, it returns to the far corner/border of the PCB editor by itself.
I have tried all the "placement modes" for component placement, but that didn't solve the problem. Interestingly, there is no such problem in my other projects. You can see everything clearly in my video that I have uploaded.
If anyone has encountered this problem, please help me!