Layers offsetted on Y axis randomly

Hello everyone, I am new to 3d printing, I started 2 weeks ago when I received a Ender 3 Neo. I didn't even start printing and already upgraded the PTFE tubing to a Capricorn branded one and also changed the glass plate to a texturized magnetic PEI plate since I am printing in PETG.

I am printing a file I have CAD designed and I have noticed at at the very begining and very end of the print, the layers are straight and are offsetted by a bit on the Y axis. I will include an image for reference with red lines depicted the Z level where the offset occured on Y. I have read that the pullie wheels or tension in belts could cause that but I have tuned it not even a week ago when I started using the printer.

https://drive.google.com/file/d/1-bh...w?usp=drivesdk

What could cause such behaviour?

Printing at 245C and bed at 80C.

Thanks a lot!