Frustrated customer

Not sure how Cell C operates, but I've been complaining since the start of November 2018 that our home fixed LTE-A service is severely lacking. I've logged cases, but Cell C magically resolves the cases by not giving any resolutions. I have all the reports from running speed tests each day in November that we get a constant 0.3mbps Down / 0.2Mbps Up. Sometimes zero Down/Up. I do understand that its a LTE service and I share the tower with many users, but I have not had this issue 14months into the contract until November. I have 100% signal testing via two routers, and two different LTE-A enabled smartphones via x5 different sim cards. All have the latest firmware. And to top it off, today my internet on my phone has completely stopped. This is so frustrating. I've called your call center so many times. I've been a loyal customer to Cell C since mid 2017 and I'm starting to regret ever switching networks. AND I have NEVER skipped a payment. What is the point of buying 300GB data per month if I cannot use it?!