XBeach wave simulation error - Forum - Delft3D Flexible Mesh

 I'm new to XBeach and I'm trying to learn by myself how the model works. Despite that I keep getting the same error again and again and really don't know why.

  Quit XBeach since computational time implodes/explodes
  Please check the velocities at the end of the simulation
  dtref   1.12948787245309
  par%dt   299.393819052059
  An extra output timestep is created to inquire the last timestep
      before an error occured