Want help with improving coverage

Nicky from Powerline originally sold us on VOX fibre. She was fantastic and said she would provide excellent after sales support, but since the order, she has ghosted me. Last week I asked her for advice as to how to improve my signal at home and she promised to call back within 10 minutes. That was 4 days ago. I called again about 3 hours later and was sent an sms saying she would call back later. I sent her an sms saying I had requested a free onsite assessment from VOX but asking what her thought on mesh were. I have yet to hear back from her or from VOX regarding the onsite assessment despite calling VOX and being told a ticket had been opened (but there was no ticket open on my app). Please will someone help?