ESP8266 server only serves page once, sometimes twice

In this state, requests for status.json look like this:

] "\r\n" <--- "\r\n"
] "+IPD" <--- "+IPD"
] "+IPD,2,3" <--- ",2,3"
] "+IPD,2,378:GE" <--- "78:GE"
] "+IPD,2,376:T /st" <--- "T /st"
] "+IPD,2,371:atus.j" <--- "atus.j"
] "+IPD,2,365:son H" <--- "son H"
] "+IPD,2,360:TTP/1" <--- "TTP/1"
] "+IPD,2,355:.1\r\nHo" <--- ".1\r\nHo"
] "+IPD,2,349:st: 1" <--- "st: 1"
] "+IPD,2,344:92.168" <--- "92.168"
] "+IPD,2,338:.2.10" <--- ".2.10"
] "+IPD,2,333:2\r\nCon" <--- "2\r\nCon"
] "+IPD,2,327:necti" <--- "necti"
] "+IPD,2,322:on: k" <--- "on: k"
] "+IPD,2,317:eep-al" <--- "eep-al"
] "+IPD,2,311:ive\r\n" <--- "ive\r\n"
] "+IPD,2,306:Cache-" <--- "Cache-"
] "+IPD,2,300:Contr" <--- "Contr"
] "+IPD,2,295:ol: ma" <--- "ol: ma"
] "+IPD,2,289:x-age" <--- "x-age"
] "+IPD,2,284:=0\r\nAc" <--- "=0\r\nAc"
] "+IPD,2,278:cept:" <--- "cept:"
] "+IPD,2,273: text" <--- " text"
] "+IPD,2,268:/html," <--- "/html,"
] "+IPD,2,262:appli" <--- "appli"
] "+IPD,2,257:cation" <--- "cation"
] "+IPD,2,251:/xhtm" <--- "/xhtm"
] "+IPD,2,246:l+xml," <--- "l+xml,"
] "+IPD,2,240:appli" <--- "appli"
] "+IPD,2,235:catio" <--- "catio"
] "+IPD,2,230:n/xml;" <--- "n/xml;"
] "+IPD,2,224:q=0.9" <--- "q=0.9"
] "+IPD,2,219:,image" <--- ",image"
] "+IPD,2,213:/webp" <--- "/webp"
] "+IPD,2,208:,*/*;q" <--- ",*/*;q"
] "+IPD,2,202:=0.8\r" <--- "=0.8\r"
] "+IPD,2,197:\nUser-" <--- "\nUser-"
] "+IPD,2,191:Agent" <--- "Agent"
] "+IPD,2,186:: Moz" <--- ": Moz"
] "+IPD,2,181:illa/5" <--- "illa/5"
] "+IPD,2,175:.0 (W" <--- ".0 (W"
] "+IPD,2,170:indows" <--- "indows"
] "+IPD,2,164: NT 6" <--- " NT 6"
] "+IPD,2,159:.3; WO" <--- ".3; WO"
] "+IPD,2,153:W64) " <--- "W64) "
] "+IPD,2,148:Apple" <--- "Apple"
] "+IPD,2,143:WebKit" <--- "WebKit"
] "+IPD,2,137:/537." <--- "/537."
] "+IPD,2,132:36 (KH" <--- "36 (KH"
] "+IPD,2,126:TML, " <--- "TML, "
] "+IPD,2,121:like G" <--- "like G"
] "+IPD,2,115:ecko)" <--- "ecko)"
] "+IPD,2,110: Chrom" <--- " Chrom"
] "+IPD,2,104:e/41." <--- "e/41."
] "+IPD,2,99:0.227" <--- "0.227"
] "+IPD,2,94:2.118 " <--- "2.118 "
] "+IPD,2,88:Safar" <--- "Safar"
] "+IPD,2,83:i/537." <--- "i/537."
] "+IPD,2,77:36\r\nA" <--- "36\r\nA"
] "+IPD,2,72:ccept" <--- "ccept"
] "+IPD,2,67:-Encod" <--- "-Encod"
] "+IPD,2,61:ing: " <--- "ing: "
] "+IPD,2,56:gzip, " <--- "gzip, "
] "+IPD,2,50:defla" <--- "defla"
] "+IPD,2,45:te, sd" <--- "te, sd"
] "+IPD,2,39:ch\r\nA" <--- "ch\r\nA"
] "+IPD,2,34:ccept" <--- "ccept"
] "+IPD,2,29:-Langu" <--- "-Langu"
] "+IPD,2,23:age: " <--- "age: "
] "+IPD,2,18:en-US," <--- "en-US,"
] "+IPD,2,12:en;q=" <--- "en;q="
] "+IPD,2,7:0.8\r\n" <--- "0.8\r\n"
] "+IPD,2,2:\r\n\r\nOK" <--- "\r\n\r\nOK"
] "OK\r\nLink\r" <--- "\r\nLink\r"
] "\n" <--- "\n"
json
["AT+CIPSEND=2,64\r\nHTTP/1.0 200 OK\r\nServer: Espruino 1v76\r\nContent-Type: text/plain"
] "bu" <--- "bu"
] "busy" <--- "sy"
] "busy inet" <--- " inet"
] "busy inet...\r" <--- "...\r"
] "\n\r\nERRO" <--- "\n\r\nERRO"
] "ERROR\r\n\r\n" <--- "R\r\n\r\n"
] "wrong sy" <--- "wrong sy"
] "wrong synta" <--- "nta"
] "wrong syntax\r\n" <--- "x\r\n"
] "\r\nERRO" <--- "\r\nERRO"
] "ERROR\r\n\r\n" <--- "R\r\n\r\n"
] "wrong s" <--- "wrong s"
] "wrong synt" <--- "ynt"
] "wrong syntax\r" <--- "ax\r"
] "\n\r\nE" <--- "\n\r\nE"
] "ERROR\r" <--- "RROR\r"
] "\n" <--- "\n"
["AT+CIPSEND=2,64\r\n\r\n\r\n{gtg:true,dtf:false,missiles:[\"armed\",\"armed\",\"repair\",\"moth"
] "bus" <--- "bus"
] "busy " <--- "y "
] "busy inet." <--- "inet."
] "busy inet...\r\n" <--- "..\r\n"
] "\r\nERROR" <--- "\r\nERROR"
] "ERROR\r\n\r\nw" <--- "\r\n\r\nw"
] "wrong syn" <--- "rong syn"
] "wrong syntax\r" <--- "tax\r"
] "\n\r\nER" <--- "\n\r\nER"
] "ERROR\r" <--- "ROR\r"
] "\n\r\nwr" <--- "\n\r\nwr"
] "wrong s" <--- "ong s"
] "wrong synt" <--- "ynt"
] "wrong syntax\r" <--- "ax\r"
] "\n\r\nE" <--- "\n\r\nE"
] "ERROR\r" <--- "RROR\r"
] "\n" <--- "\n"
["AT+CIPSEND=2,9\r\nballed\"]}"
] "bus" <--- "bus"
] "busy i" <--- "y i"
] "busy inet" <--- "net"
] "busy inet..." <--- "..."
] "busy inet...\r\n" <--- "\r\n"
["AT+CIPCLOSE=2\r\n"
] "\r\nERROR\r\n" <--- "\r\nERROR\r\n"
] "bu" <--- "bu"
] "busy " <--- "sy "
] "busy in" <--- "in"
] "busy inet." <--- "et."
] "busy inet...\r" <--- "..\r"
] "\n\r\nER" <--- "\n\r\nER"
] "ERROR\r" <--- "ROR\r"
] "\n" <--- "\n"
> 

What is going on? Does anyone know how to fix this?