1. With a timing tools it is still possible to flip the camshaft 180 degrees out. But this should crash the valves into pistons a bit.
2. Head gasket job was done improperly, skimming, valves not sealing (+lash), overall cleanliness, pistons, rings. Did you literally just swapped the gasket?
3. Wiring was damaged during process. Or sensors. Or phonic wheel, or the "phonic wheel"-like thing on the camshaft (how do you call this feature?).
4. Do not just throw new parts at the car. This is lame, amateurish. Diagnose it:
https://www.youtube.com/c/AutomotiveTestSolutions/videos
Example of timing waveforms (there is Doblo 1,4 8V same as Grande/EVO):
https://rotkee.com/en/waveform-library?brand=169
5. Normally, bad (or unpluged) camshaft sensor results in RPM limit (2500-3000 or so). But the car is driving fairly good (NO rough idle), maybe has less power.
6. If you are total lame, you can even install the phonic wheel wrong (regardless the small dimple which positions it - "clocking").
7. If you swap the crankshaft seal, you can crack the timing belt wheel/cog, the "key" will pop. YouTube, german video "Punto Zahnriemen-Desaster".
8. Other things. Mechanical, electrical, fuel delivery, air, etc.
9. Oil. Hydraulics, V.V.T.
10. Electronics, ECU. Check the OBD2 faults, peep the parameters (if all make sense). Note, this is a last point you do, not 1st (like most would).
This is not a simple job for beginner, although the engine is easy, perfect for DIY, hobbyists. But...there is a big "But"...
