Delays

[OH25]

I got to Winson Green tram stop today at 8:45 and a tram didn't turn up until about 9:10
There was about 5/6 trams going towards Birmingham but none coming in my direction
Something happened because there was a tram at the stop, one further down the line, another one at Soho Benson Road and were all at a stand still for about 5ish minutes
does anyone know why this happened?
it was a real nuisance.