Nozzle clog

[MStar]

I have an Ender 3v2 since a week. At first my prints were great, buter now I've had a clogged nozzle 2 days in a row. Does anyone know how to prevent this?

I watched tutorials on youtube to prevent this but it doesn't work.
Things I have done:
Install metal extruder and capricorn PTFE tube
Upgraded bowden couplers
Turning the coupler back one turn, installing PTFE tube and fastening it afterwards at 200 degrees temperature

https://drive.google.com/file/d/16nGs1T4syRf_6A3l4731B35QKkx_0DGB/view?usp=sharing

Can anyone help me prevent nozzle clogs?