Hi @Adelaide , welcome to the forum! Please upload your invest logfile and take a look at Guidelines for posting software support questions
Can you be more specific? Maybe the logfile will indicate the problem here.
The runtime will depend on the extent of the study area and also the resolution of your input rasters. But it’s also possible that some problems with input data could result in the model trying to do a lot more work than it should.
If the logfile doesn’t give us any clues, we will probably ask you to share your input data as well.
Best,