I observed a drop in MTN network in my area for some days now. im thinking may be it's general. Hope it's not the same there.

Lol.
Their network is still just as the same. They only give poor network whenever they deduct your airtime and convert it into their criminal, dubious and unsolicited bonuses.
They recently did the same to me till I figured out their cunningness, so I recharged and bought a data subscription package and it's been back to normal ever since.

I urge you to do the same, or stick with a network that won't defraud you. E.g GLO