Poor service

Utterly garbage internet as of late, i have a 250mb line via axxess, the last couple of weeks my pings have been jumping from between 12ms to 400ms and my internet also drops every now and then, i need my internet in order to do my work, currently i have to run on mobile data due to the connection being so poor, everytime i log a ticket i get told to go and connect my laptop directly to the ONU instead of support having a look on they're system, my ONU is behind the tv cabinet , i cant move that cabinet on my own and i also do not have time to go and struggle with that, i have rebooted both my router and my ONU, will Axxess please sort out the issue or should i look for a different isp