Initial values error using mapped mesh

Hello,

Every time I try to use a mapped mesh for a time dependent simulation I have the following error :
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The following feature has encountered a problem :
failed to find consistent initial values.
System matrix is zero.
Last time step is not converged...
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It is weird because when I run the same simulation with a mesh generated by default, everything works fine.
My geometry is more or less a rectangle (3D).

Is there anything special to do with the initial condition when a mapped mesh is used ? I don't find anything on the web.

Thank you for your help.