I recently purchased a set of Soundbud Slims on Amazon UK. They worked fine with my iPhone 7 (on iOS12.x, 13, 13.1 and 13.1.1) but will not connect to my iPhone 11 (on iOS 13, 13.1 and 13.1.1). Other devices can connect to the 11 via Bluetooth with no issues.
Reading through, this seems to be an issue with the Soundbuds rather than the iPhone itself, would this be correct?