Mac to USB flash - slow transfer speed

I am trying to copy a large file to an USB flash drive and for some reason the Mac is transfering the file to the flash drive with a speed of < 10Mb/s. I transfered files before between this Mac and that same flash drive and I never had this issue before.

How can I speed up the transfer?

Trying different ports hasn't helped. Someone suggested to prevent Spotlight from searching the USB flash drive which I did but the transfer is still slow.

I am using an M1 MacBook Pro with macOS 11.5.2.