My guess is that your autorouter setup is wrong.
1) Fine-pitch components should be aligned with the grid (all pads);
2) Routing grid should be (at least) equal the pitch of fine-pitch
components. If the pitch is not an exact routing grid multiple (ex.:
pitch=0.50mm and routing grid = 0.25mm), then you need a very small routing grid
to route the PCB.
3) DRC clearance should be smaller than the pitch minus the trace width
(space is needed for the trace to get to the pad). At least for the
clearance between the wires it should be in accordance to this rule.
Also have a look at this site:
https://intranet.ee.ic.ac.uk/t.clarke/eagle/Eagle_configuration.htm