Damp proofing failure within guarantee

[stargazerlil]

It’s failed really quickly within. A few months, cam with a guarantee for 10 years. In this case repeating work will not fix the issue, they didn’t assess what needed to be done correctly. Can I expect a refund? What can I do to get one, go to the ombudsman?

You need to read the terms of the guarantee and then apply to whomever issued it for next steps - probably an initial assessment and then remedial works (not necessarily repeating the works, depends on what the best remedy is). You cannot go to the Ombudsman until you have exhausted the local process for complaint.