Dissappointed that service so bad.

My friend has been asking for a settlement letter on 29 April 2025 which we only got on 5 May 2025, now we have been phoning and phoning since 8 May 2025 and asked for a paid up letter on money which was paid already on 7 May 2025 and still no feedback. We eventually got through on the phone and requested it on 8 May but nothing yet and emails to the customerservice has yielded no response , even the 29 April ones...How do a person get serve from this company?