Hi @Bachelorproef you should read the below two tutorials for topics regarding artifacts.
https://neuroimage.usc.edu/brainstorm/Tutorials/ArtifactsDetect
https://neuroimage.usc.edu/brainstorm/Tutorials/ArtifactsSsp
If you did artifact rejection > bandpass filter and/or resample, the artifact rejections should be there still. You may need to select process entire fill at once for files with SSP (if you did artifact rejection with SSP).