Unable to connect to a website (Time out)

I've recently stopped being able to connect to a set of websites ie sheffield.bcss.org.uk, leeds.bcss.org.uk etc. I've tried flushing DNS, resetting router etc. The sites work ok on 5g.  It only works when I use a VPN.

IP4 82.42.165.17

Tracing route to sheffield.bcss.org.uk [185.215.37.8]
over a maximum of 30 hops:

  1     3 ms     2 ms     2 ms  192.168.0.1
  2    15 ms    11 ms    10 ms  10.53.35.169
  3    17 ms    13 ms    13 ms  80.255.198.182
  4     *        *        *     Request timed out.
  5     *        *        *     Request timed out.
  6    18 ms    14 ms    14 ms  tcma-ic-2-ae9-0.network.virginmedia.net [62.253.174.178]
  7    19 ms    14 ms    15 ms  ge-1-1-0-core1.tckbn.uk.as6908.net [195.66.244.13]
  8    18 ms    13 ms    13 ms  62.149.57.183
  9    21 ms    18 ms    16 ms  62.149.57.226
 10    21 ms    16 ms    15 ms  62.149.57.133
 11    18 ms    19 ms    16 ms  ae9.core0.sdsdn.uk.as6908.net [62.149.57.143]
 12    21 ms    17 ms    14 ms  xe-0-0-0.edge13.sdsdn.uk.as6908.net [62.149.56.101]
 13    23 ms    18 ms    16 ms  swift468.swiftinter.net [185.215.37.8]