Supermarkets are very busy and it is sometimes hard to get deliveries. You may have to keep trying.
If you are a person at increased risk you can register with the government as vulnerable. This can help you access help getting food. Supermarkets should be contacting people on this list shortly to offer delivery slots.
If you live in Leeds, you can get help via Voluntary Action Leeds who are coordinating volunteers to help with delivering food and medicine and health needs. You can register by calling 0113 378 1877.
If you are still worried, particularly if you are in University accommodation and there are fewer staff on site please contact Help and Support.