Yo guys

I am not that familiar with apple devices since I'm more of an android person sooooo can you please help me with this?

So, my imessage was being really slow and annoying so I checked out the internet for some solutions and deactivated it for like a minute or so. When I signed in, it said that my username/password is incorrect and I'm like "WTF"

so I reset my password after about a dozen tries and tried to sign in to it again but IT DIDNT WORK.

I signed in to iTunes with the same username and password I entered in imessage and IT FREAKING WORKED. but when I tried on facetime, it didn't.

can someone please help me with this? I seriously need to contact my classmates and teachers since my exams are starting on Monday :(