Joy Division were an English post-punk band formed in 1976 in Salford, Greater Manchester. Originally named Warsaw, the band consisted of singer-songwriter Ian Curtis, guitarist and keyboardist Bernard Sumner, bass player Peter Hook and drummer Stephen Morris. The band was formed by Sumner and Hook after attending a 4 June 1976 Sex Pistols concert at the Lesser Free Trade Hall in Manchester. While Joy Division's early recordings were heavily influenced by early punk, they evolved a unique sound, aided by producer Martin Hannett, which earned their reputation as pioneers of the post-punk movement.

Joy Division toured Continental Europe in January 1980. Although the schedule was difficult and demanding, Curtis experienced only two grand mal seizures, both in the final two months of the tour. That March, the band recorded their second album, Closer with Hannett again producing at London's Britannia Row Studios. That month they released the "Licht und Blindheit" single, with "Atmosphere" as the A side and "Dead Souls" as the B side, on the French independent label Sordide Sentimental.  A lack of sleep and long hours committed to the bands' activities destabilised Curtis's epilepsy, and resultingly, his seizures became almost uncontrollable. Curtis would often experience seizures during live performances, which would leave him feeling both ashamed and depressed. As the band worried about their singer, some audience members thought his seizures and behaviour were simply part of the show. On 7 April, Curtis attempted suicide by overdosing on his anti-seizure medication; phenobarbitone. The following evening, Joy Division were scheduled to play a gig at the Derby Hall in Bury. Curtis was too ill to perform, so at Rob Gretton's insistence, the band played a combined set with Alan Hempsall of Crispy Ambulance and Simon Topping of A Certain Ratio singing on the first few songs, with Curtis singing for part of the set. When Topping came back towards the end of the srt, some audience members threw bottles at the stage. Curtis's ill health lead to the cancellation of several other gigs that April. Joy Division's final live performance was held at the University of Birmingham's High Hall on 2 May, and included their only performance of "Ceremony", one of the last songs written by Curtis and later recorded by New Order as their first single.  Hannett's production has been widely praised. However, as with Unknown Pleasures, both Hook and Sumner were unhappy with the production. Hook said that when he heard the final mix of "Atrocity Exhibition" he was disappointed that the abrasiveness had been toned down. He wrote; "I was like, head in hands, 'Oh fucking hell, it's happening again. Unknown Pleasures number two...Martin [Hannett] had fucking melted the guitar with his Marshall Time Waster. Made it sound like someone strangling a cat and, to my mind, absolutely killed the song. I was so annoyed with him and went in and gave him a piece of my mind but he just turned round and told me to fuck off".

Using a quote from the above article, answer the following question: How did the other members feel
the band worried about their singer,