Are the pipes old cast iron? Possibly buildup in the pipe or maybe rust clogging the area right at the valve connection. The screw just holds the knob in place.
I believe they are PVC. I know my father had a hard time with the hot water one and replaced the knob multiple times & even replaced the cartridge. Pretty sure it's never been the correct cartridge. I took pictures & tried to upload them but it didn't go through (due to my internet being crappy).
Internet was out for over 6 hours.
Mine was out for over 12 hours the other day & I spent 4 hours on the phone on hold trying to get through to customer service. There was music and every 15 seconds it repeated a message about going online to their website & how the call was important and they would be with me shortly. Just after the 4 hour mark the message changed and said I reached the office after business hours & to call back later. Then it asked me to complete a customer satisfaction survey & hung up on me. I called back to get a message saying there was a network outage in my area. Mind you, when I initially called, it said my expected wait time was 48min. But, since it is satellite, they will not give $ in compensation for an outage. I've tried. Although, I should probably argue more next time. In the past they would give me extra Gb of data but they are no longer the same company now. They are now called Viasat. I saw them advertising an "unlimited" plan-- which is bogus. They don't do "unlimited".
I went to visit a friend today & got to watch the plight of the carpenter ant on the pavement of his car port. It was trying to move a wet grain of rice that was almost the same size as it's body but it couldn't budge it. After 10 min it started to budge but then the yorkiepoo ran up, pushed the ant aside with her nose, and ate the rice. Cue the ant to totally lose it's mind & run in circles-- just totally freaking out. Friend's gf took pity on it and saw another smaller grain of rice. She put it down in front of the ant, and it calmed down. It was able to pick the new piece of rice up and it then took a convoluted path off of the pavement, in to the grass, and under the leaves.
Also took apart cardboard boxes (Mom had an Amazon shopping spree for Prime day), cleaned up some trash, cleaned the counter in the kitchen, & picked up cat litter from the store. Heat index was 111 so I didn't stay out too long.
Edit: Finally got the pics to load.
The pipes are either PVC for cold & CPVC for hot or they could be galvanized. I would have to move furniture & remove a wall panel to look & my friend borrowed my prybar & hasn't returned it.