Hello
I have been working on an animation on Krita and until now whenever I tried to play the animation it worked perfectly fine. But as I was working on it today, I suddenly could not play it anymore. Whenever I tried, the message "regenerating cache... elapsed: 00:00, estimated: 00:00. Memory limit is reached! The number of clones is limited to 0." popped up. I just started animating not too long ago, so I don't really have any idea what this means.
Is there any way to fix this issue?

Thanks in advance for your answer!

Which version of krita and which operating system are you using?
How much RAM does your computer have?

What is the size in pixels of your image? How many layers and keyframes do you have?
How long is the animation (frame length)?

How big (RAM usage) is your animation in krita? The status bar along the bottom of the main window has a RAM usage indicator and will give more details if you hover your cursor over it.

In situations like this, it's a good idea to not have any other applications running while you're working on your animation.

I'm using Version 4.1.5, my operating system is Windows 10 and my computer has 16GB RAM.

The image size is 3508 x 2480 pixels and there is one layer with around 900 frames.

The RAM usage is 7.1 GiB.

The latest formal release of krita is 4.2.9 and you really should use that. It's available here: https://krita.org/en/download/krita-desktop/
It has many bug fixes and improvements compared to older versions.

Your animation's current RAM usage may be the basic cause of the problem. By default, krita allocates itself 50% of your available RAM for its own storage purposes. i.e 8GB in your case.

If you go to Settings -> Configure Krita -> Performance section, then on the General tab you can adjust the amount of RAM available to krita. I have mine set to 75% of 16GB = 12GB.
I'm assuming that you haven't already done that.

You have to leave at least 2.5GB of RAM available for Windows and the krita application itself.
If you render an animation out then ffmpeg can take up quite a bit of RAM while it's rendering.
It's instructive and interesting to use the Task Manager to see how much RAM is being used by which processes and applications when you're doing animations.

You might think that krita's own swapping would take care of all this but I believe there are some difficulties with it. A developer would be needed to comment on that.

If you have these kinds of size limit problems, you can try scaling your image size down though I realise you may not be happy with that.
If, due to your painting and animating technique, you have lots of unintentional or not needed off-canvas content (which can push up image storage requirements), you can get rid of it by Image -> Trim To Image Size. You may want to try that to see if it reduces your RAM usage and file size too, but only if you're not deliberately using and relying on off-canvas content as part of your working technique.

In general, for long and large animations, it's a good idea to use krita for short segments and to use an external video editor, such as Kdenlive or whatever to join them all together.

Okay I tried it and it worked! thank you so much!