Below is the answer I got from the GC:
Thank you for contacting the Gambling Commission on 23 November 2016 regarding
www.mondogoal.com operating under the licence of operator Mondogoal Trading Limited.
From your correspondence we can see that you have been experiencing problems with withdrawing funds from your account for two months. Whilst we can see that you have contacted the operator on several occasions regarding this matter it is not clear if you have followed their complaints process.
If you have not complained to the operator then you will need to do so. Further advice on how to make a complaint can be found on our web-site here.
From reading your email it is clear that you have gambled online, the complaints procedure can also be found in the terms and conditions that you agreed to upon opening your account. Please see the terms and conditions here. So that your complaint is handled as quickly as possible, you should always follow the licence holder’s complaints procedure which can be found in their terms and conditions (Dispute Resolution and Governing Law), including any Alternative Dispute Resolution service (ADR). Mondogoal's nominated ADR is ADR Group.
Please note that it is not within our legal power to become involved in individual complaints and we cannot help you get any money back that you may have lost.
We hope this clarifies your query and our role.