Request url not picking up collection variable in Monitors

Hi,
I am picking the Account ID in request url which is stored in collection variables and then performing DELETE operation. When I run it manually it works fine but when a monitor is setup for the collection the DELETE operation fails as the Account ID value is not picked up in the request url. Can someone please guide why the value is not picked up from collection variable and the solution for this?

I tried to store the value as environment variable but still the same issue is observed.