Disconnected with an upgrade

I am very disappointed I've been using rain since 2021 and all was well until I received a call from them for an upgrade to 5G. Had no problem hence it was on special. An Agent by the name of Brandon called and he assisted with an upgrade to 5G before we continue he asked to to cancel the 4G first on my side and explain that am upgrading to 5G I asked him if I won't get disconnected on 4G he said no until on the 25 of December to my surprise after two days I was disconnected Now this messing up with my job hence am still working at home. I tried to call but failed. Only today receiving a call from courier company that my upgrade package will be delivered next week really it can't be accepted am working at home and I can't be absent from work whole week. Can you guys fix this ASAP IT seems like BRANDON just wanted to make a sale and forgot that it affecting me on my side.