I had 50/35 plan for years and I recently found that the actual speed was 15/0.2. Verizon sent me the technician two times to solve the issue. After two visits and 6 hours spent on the issue by a technician, the speed came up to 50/2.5. The upload is still not solved yet. The technician said the building I live uses DSL, not fiber, and the maximum I can get would be 10 Mbps. He suggested me to downgrade the plan then I will get the upload speed up to 10mbps.
I downgraded my plan to 15/5 by paying extra $5/months than my old 50/35 plan, and I tested the upload speed again. It's 15/2.4 now, which is very depressing result that I essentially paid more to downgrade the plan by following the technician's advice for the same speed. Verizon should higher my upload speed to 5mbps as supposed to be, or I will soon drop my membership after being a customer for 5 years with Verizon.