Please inform me of the specific circumstances. If only the PNG diagram alone, it should not result in the situation you described. Are you employing plugins such as multilayer? I can recall quite a few multilayer plugins that are incompatible with multi-frame animation plugins.
Please show me the file name and plugin settings. Such a situation shouldn't have occurred to you. This should be the case where the picture is cropped. Also, when using this plugin, it is necessary to pay attention to rearranging the picture, and it needs to be changed to the mode of three groups on the top and three groups at the bottom. The top three sets are standby, walk, and run. The next three are 45 on standby, walk, and run.