Toilet and Bathtub issue

[ShitShowIRL]

upstairs toilet been clogging on and off, won't plunge or drain and has been backing up into the upstairs bathtub through the drain. Everything downstairs is okay. Any advice and help would be appreciated

 

[TomFOhio]

Sounds like the main line going to the downstairs is plugged. When you flush the toilet and it comes up the
tub means it can't get downstairs. You will need it snaked out probably by a professional drain
cleaning company. Make sure you tell them on the phone that its upstairs on the second floor.