In Love with Alma Cogan (2011)

The film revolves around, Norman, a world-weary manager of a pier theatre in a seaside resort. Norman has worked in the theatre for all of his life, but will not accept that the local council, which own the theatre are planning to install more commercial management in an attempt to boost audience numbers. As the story unfolds he realises it may be time to move on and put behind him the ghost of 50s & 60s singer Alma Cogan, who performed at the theatre many years ago. Sandra, his devoted long-suffering assistant and Norman decide to leave the theatre to fulfill her dream of being a professional singer and unexpectedly enjoying a late blossoming romance. From Wikipedia.

Unfortunately the movie In Love with Alma Cogan is not yet available on HBO Max.