Lead tracking suddenly stops

I have Mautic running for almost three weeks now.

Lead Tracking suddenly stopped at 9 AM today, with no appearent reason.

Tracking .gif is in the pages but no visitors are tracked.

One may suspect an incorrect URL, but Form submissions work as expected, so that should not be the case.



I’m using WordPress 4.4.2 with WP Mautic 1.0.1.



I can see in my apache2 access logs that I have visitors who are serviced with pages as expected.

I have no clue to where to start looking for the problem.



HELP!

I have Mautic running for almost three weeks now.
Lead Tracking suddenly stopped at 9 AM today, with no appearent reason.
Tracking .gif is in the pages but no visitors are tracked.
One may suspect an incorrect URL, but Form submissions work as expected, so that should not be the case.

I’m using WordPress 4.4.2 with WP Mautic 1.0.1.

I can see in my apache2 access logs that I have visitors who are serviced with pages as expected.
I have no clue to where to start looking for the problem.

HELP!