I see 4 dots, meaning you are using 4 mesh objects. bridge loopswill only work inside a single mesh object, with at least two loops.
These loops must have the same number of vertices!
FedPete seems to have spotted the problem. And solution. The ‘loops’, your circles, need to be one object not several, then edit mode will join them all when selected.
Generally it helps to give full screenshots, as there can be info like what mode you are in visible. Other settings etc.