Fit to fill (Change clip speed) Grayed out?!?!? But manual Time remapping (blue arrow) works fine??

Update: I'm still having this issue in v25 when auto-transciption is enabled. Turning off transcription makes "fit to fill" and 4-point editing dialogue box options available again, but when I'm text-based editing and want to use "fit to fill" I must turn off transcribe features to activate the 4 point edit. Not critical, just annoying. 

I am having this issue too, using Premiere 24.6.1 (build 2) on Apple M3 Max. I've also tried creating a brand new project, recutting in the clip, resetting all 4 points, checking durations, replacing the proxy clip with full res, etc. etc.  No other effects on timeline clip. You are not crazy -- 'fit to fill" is not available (grey) in Fit Clip dialogue box!

I'm having the same problem. Windows 10, Premier Pro Version 24.4.1 (Build 2).

I have narrowed down the issue enough to replicate it. What's happening for me is this:

1. I open a project. I have one Sequence with one video track (source patching and track targeting is ON) and two audio tracks (source patching and track targeting is OFF), none of them are synced.
2. I set an In and Out point for the Sequence on the timeline and I leave the playhead marker at the In point.
3. In the Project panel, I double click on the clip I want to insert.
4. I set the In point and the Out point for the Clip in the Source panel.
5.  I tap the period key to Overwrite. The Fit Clip options appear, and all options are available, including Change Clip Speed (Fit to Fill)
6.  I select "Change Clip Speed". It works perfectly fine.
7.  If I undo or attempt to repeat these exact same steps a second time, Change Clip Speed is now greyed out, no matter what I try. 
8.  I close the project without saving anything and reopen it.
9.  Repeat. The exact same thing happens.

It seems that Change Clip Speed works fine. Once. After that, it's greyed out until I close and reopen the project.

However, after writing out these steps, I tried it again and it works fine, even if I undo / redo / repeat / try again on a different part of the timeline. So... now I can't replicate the issue apparently? Premiere is haunted I guess. 😂 I'm still posting this info in case it's helpful to anyone. 

Working here also...

Win 23H2, PP: 24.3

A fit-to-fill edit requires an In and Out marking the source clip AND an In and Out marking where it goes in the timeline.

check here for more details:

https://larryjordan.com/articles/create-a-fit-to-fill-edit-in-adobe-premiere-pro/

take off all effects applied, either apply them on adjustment layers or use nesting workflows,

so:

01. always try to finish your editing without any effects applied

02. do your speed stuff

03. apply effects on adjustment layers or nest your edits then apply effects to nested.

04. render -> export