Merge Videos using fluent-ffmpeg

Question

I'm trying to merge two videos, the following code works perfectly on windows 10, but it gives me an error when trying to run it on linux/ubuntu, same on wsl

    async joinVideo(): Promise<boolean> {
        return new Promise((resolve, reject) => {
            signale.info('Joining video')
            const profile = path.join(__dirname, '../videos/input/profile.mp4')
            const sb = path.join(__dirname, '../videos/input/sb.mp4')

            const joined = path.join(__dirname, '../videos/profile-sb.mp4')
            const tempFolder = path.join(__dirname, '../videos/temp')

            ffmpeg({ source: profile })
                .input(sb)
                .on('end', () => {
                    signale.success('Video joined')
                    resolve(true)
                })
                .on('error', err => {
                    signale.error(err)
                    reject(false)
                })
                .mergeToFile(joined, tempFolder)
        })
    }

The error i get

Error: ffmpeg exited with code 1: Error reinitializing filters! 
Failed to inject frame into filter network: Invalid argument
Error while processing the decoded data for stream #1:0
Conversion failed!

    at ChildProcess.<anonymous> (/mnt/c/Users/Anri/Desktop/lead-gif-generator/node_modules/.pnpm/[email protected]/node_modules/fluent-ffmpeg/lib/processor.js:182:22)
    at ChildProcess.emit (node:events:517:28)
    at ChildProcess.emit (node:domain:489:12)
    at Process.ChildProcess._handle.onexit (node:internal/child_process:292:12)

the installation of fluent-ffmpeg should be correct as other operations are working, only mergeToFile function is erroring out

also strange thing is that if i put same file in both inputs it works fine, my guess it happens because of differance between videos, but why it works on windows