WowAce

What version of Grid2  are you using (Version is displayed in General/About Tab) ?

 2.0.73

What game client version, classic or retail, windows or mac and language are you using ?

 retail

What steps will reproduce the problem?

  joining to a group, but sometimes its well positioned sometimes its not
Did you try having Grid2 as the only enabled addon and everything else disabled?

  yes

Was it working in a previous version? If yes, which was the last good one?

  yes, before the prepatch

Do you have an error log of what happened? If you don't see any errors, make sure that error reporting is enabled (`/console scriptErrors 1`) or install [BugSack](https://mods.curse.com/addons/wow/BugSack).

  it didnt give me an error

Please provide any additional information below.

 here is a video about the case: https://vimeo.com/779193948

This happens if you are in combat, frames cannot be moved/aligned while in combat due to game restrictions. You can use a left or right alignment instead of center as workaround.

I see, where can you change to it to left alignment?

General/appearance/layout disposition tab:

Look for layout and group anchor options.

If your profile uses themes, you have to look for the appearance tab in each theme.

I found it thanks! Its a bit off, but is there any way to make a script (in weakauras for example) that reloads the theme after you get out of combat? If you could provide the code that reloads the themes, then I'd be grateful and do the rest!

Grid2 should  realign/readjust the frames after the combat ends, but it seems in the video the frames were not realigned, can your repeat this behaviour or is it random ? Because the game occasionally glitches with the combat mode.

Unfortunately it happens like 50% of the time when I join to a group. 

50% is a lot, it never happened to me, can you send me you profile ?  You can export the profile to text format going to Profiles/Export&Import.

Here is my profile: https://pastebin.com/ZjtGvqH8

I took your advice and changed the alignment and seems to be working right now, but dont forget to change it back for testing purposes.