  We present the results of our analysis of Gaia19dke, an extraordinary
microlensing event in the Cygnus constellation that was first spotted by the
{\gaia} satellite. This event featured a strong microlensing parallax effect,
which resulted in multiple peaks in the light curve. We conducted extensive
photometric, spectroscopic, and high-resolution imaging follow-up observations
to determine the mass and the nature of the invisible lensing object. Using the
Milky Way priors on density and velocity of lenses, we found that the dark lens
is likely to be located at a distance of $D_L =(3.05^{+4.10}_{-2.42})$kpc, and
has a mass of $M_L =(0.51^{+3.07}_{-0.40}) M_\odot$. Based on its low
luminosity and mass, we propose that the lens in Gaia19dke event is an isolated
white dwarf.
