Hi Fadel.
The issue of croissant dough shrinking when rolled out is common and is usually related to gluten elasticity. Here are a few points to consider:
-The dough should have adequate resting time.
-Avoid overworking the dough.
-Make sure the dough is cold enough when working with it.
-Use a flour with the appropriate protein content for laminated doughs (around 12 to 13%). As the recipe suggests, use a flour with a 0.4 / 0.7 P/L ratio for elasticity. For croissant dough, using flour with a P/L ratio between 0.4 and 0.7 is ideal for controlling elasticity. This ratio refers to the balance between the strength (P) and extensibility (L) of the dough. This will ensure good gluten development without making it too strong.
By implementing these techniques, you should be able to roll out the dough without it shrinking as much.
I hope this information is helpful.
Best regards.