"I cannot send products to clients in picture or video format because they're too heavy for the slow internet," Makungu told DW. "Normal access comes for a very short time and when so many people are using the same network, many activities come to a standstill."
Makungu's story is shared by many young users and entrepreneurs who have turned to the internet as a source of income. The majority of young people struggle to find a regular job in Tanzania.
"We were using the internet to do a lot of things and now we are in the dark," said a young female journalist, who preferred not to be named for fear of reprisal. "What they are doing to us is very unfair."
Internet, social media slowed down
NetBlocks, an internet services watchdog, has reported "widespread disruption" to internet services in Tanzania as well as restrictions to popular social media applications, like Facebook, WhatsApp, Twitter and YouTube.
While some savvy social media users manage to bypass the restrictions by using a virtual private network, or VPN, the workaround is illegal in Tanzania.
The official requested not to be named since he was not authorized to speak about the matter.
During his first term, Magufuli was accused of cracking down on dissent and restricting freedom of the press.
Activists criticize communications slowdown
"We call upon the Tanzania Communications regulatory authority to takes steps to restore the internet because social media plays an important role in the provision of social and economic services," said Anna Henga, Executive Director of Legal and Human Rights Centre.
In a statement, the organization described the slowdown as a violation of human rights in a country whose constitution guarantees citizens the right to information via various sources, both locally and internationally.
Tanzania's communications regulator spokesperson, Sema Mwakyanjala, said the government was working in collaboration with service providers to restore the internet, although he was reluctant to say whether the authority had known about the slowdown.
"Users should communicate with service providers regarding any issues with internet access," he told DW, adding that the problem would be soon solved.
Internet central to many young people's livelihoods
Analysts say the impact of the communications slowdown has been immense. Tanzania has more than 2 million internet users and many of these, especially young people, can't earn money without the internet.
Bravious Kahyoza, a lecturer of economics at the Dar es Salaam-based Kampala International University, estimates between 15 - 27% of young people's income is made online.
E-business, especially, is growing in importance in Tanzania, he pointed out. This includes starting and coordinating projects, and getting information in real time such as how markets are trending.
But, he says, internet disruptions around the elections have limited this kind of coordination between Tanzania and other countries, Kahyoza said in a telephone interview with DW.
Muzzling free speech
Since Magufuli came to power five years ago, Tanzania has passed a raft of laws that muzzle the media and stifle free speech, analysts say. For instance, bloggers now have to register and pay expensive licensing fees of around $900.
Civicus, a civil society monitor, says Tanzania has suffered a "dramatic decline" in freedom of expression.
But President Magufuli has never appeared to be a fan of the internet, especially social media, which he sees as hindering his "Hapa Kazi tu" (Here it's just work) slogan that he's famous for.
"I was wishing that angels descend from heaven one day and close all these platforms, so that when they are reopened after one year, we have already built our new Tanzania," Magufuli said while addressing a gathering two years ago.