Dark side bars when exporting video

[gmdinei]

Hello, I acquired the action to record my gameplays, however, when exporting the video to get a smaller size, the video has dark bars on the sides and does not maintain the proportion I chose (1080p) the video is squeezed on the sides, I would like to know how to solve this problem; my video card is an MSI RX 570 8Gb, with 16 Gb ram and 8th generation intel i3 processor, thanks.

[Piotr]

Hello, what is the video size before and after exporting?

[gmdinei]

Hello, thanks for answer, I do the recording with the resolution of 1920x1080 (16: 9), but after exporting, the video is squeezed, with dimensions 4: 3 with dark side bars.

[Piotr]

Please provide us screenshots from Export Settings tab and Export Window.