Internet is so slow and get disconnected

Since yesterday 2 March, the 1Gb fiber home Internet is so slow and barely opens websites. Steaming is stopped. I have done all the possible options of restarting and resetting for both modems. The speed on fast.com comes to 50Mb but that still not stabel. zipcode is 3901PV

It is reall so annoying as I need the hignspeed and stable connection for working from home. 

Odido quality of serivce is getting worse and worse everyday

Hope to find an urgent answer and solution

Thank you