I have seen this happen several times, but it can be after either team scores straight at the start of the second half. In fact I can’t remember not seeing this happen after an early goal in the second half.
I have the same problem. I think it started after I’d changed team shape to Highly Structured. I ran a quick test with a new save and it happened again when I went to Highly Structured from within the tactics menu at halftime. iPad 2017 iOS 11.2 FM 18.1.4