Tenant not responding to make arrangements for annual gas check

Maintenance

We have an ongoing problematic DSS tenant who is not responding to make arrangements for having the annual gas check & boiler service done. We know she has received the notification by email because she responded to details regarding another matter, but now ignoring the gas service arrangements which we have been trying to arrange for the last couple of weeks. If she does not respond and does not give us an opportunity to arrange a date and access to the property, can we notify her that she would need to make her own arrangements for boiler repair & carry the costs if it breaks down in future? Also what can we do about the gas check which is about to expire soon?....she knows that the gas check is a legal requirement but is not taking much notice of this. We are not thinking of eviction yet as it is too costly for us at the moment. Any advice appreciated.