Composition pixelated after exporting

[Mariana5C2E]

I'm new to After Effects so I hope I explain this clearly.

I added small animations on a video and when I play it on After Effects and besides the video becoming slow for some reason, it looks fine. I rendered the composition and exported it to mp4, and it looks fine except for just one second when the video becomes gray and pixelated, but the shapes and text I added on After Effects looks perfect.  How should I export my composition for it to be okay and so that I can edit it on Premiere Pro too??

[Mariana5C2E]

I made a mistake, the video after exporting from Premiere Pro is when the video has that pixelated problem

[Rick Gerard]

Cropped screenshots that do not show us the modified properties of your timeline are useless in diagnosing problems. Select all your layers, press 'uu' to reveal all modified properties, and then please embed your screenshot so we can see what you are doing to the layers. We also need a detailed workflow description. The project could be Dynamic Link or a rendered DI (digital intermediate) or production master. The format of the DI render could be improperly set up and rendered as an MP4.

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