Published looking for someone to help with technical support - OJS 3.4

Good day

I am not sure if there is anyone who can assist with the below or refer to a platform where we might find a suitable provider.

We are a South Africa based publisher in need of someone to provide technical support and troubleshooting, modify certain features, etc.
The service provider that set up and hosts the software only provide minimal support but we need help with a number of issues.

We are looking for someone with the capacity to meet the diverse specifications and tight deadlines, who can assist on a case by case basis, as needed and not in a full term, employment capacity.

Any advice or referrals are welcome.
We do not require the provider to be based in South Africa.