Hi and welcome to ProRealTime and to the forum!

You are not missing anything: the platform does not ship a built-in “previous day OHLC levels” indicator, but the data is fully accessible from code. The reason LLMs struggle with this is that they tend to hallucinate Pine Script / MQL syntax (things like request.security(), != or &&) that simply does not exist in ProBuilder. The idiomatic ProRealTime way is the TIMEFRAME(daily, updateonclose) block — the same technique used in the thread you linked, just applied to the weekly timeframe there.

Here is an indicator that plots yesterday’s High, Low and EQ (the midpoint of the range). It also includes yesterday’s Open and Close as an option (set ShowOpenClose = 1 to display them):

//-----------------------------------------------------------//
//PRC_Previous Day High Low EQ
//version = 1
//10.07.2026
//Ivan Gonzalez @ www.prorealcode.com
//Sharing ProRealTime knowledge
//-----------------------------------------------------------//
// Settings
ShowOpenClose = 0 // 1 = also plot previous day Open and Close
//-----------------------------------------------------------//
// Previous day values (last completed daily candle - no repainting)
TIMEFRAME(daily, updateonclose)
pdh = high[0]  // previous day High
pdl = low[0]   // previous day Low
pdo = open[0]  // previous day Open
pdc = close[0] // previous day Close
TIMEFRAME(default)


// EQ = midpoint (equilibrium) of the previous day range
eqLevel = (pdh + pdl) / 2


// Optional Open/Close plots
plotO = pdo
plotC = pdc
if ShowOpenClose = 0 then
  plotO = undefined
  plotC = undefined
endif


RETURN pdh COLOURED(0,150,0) STYLE(line,2) AS "Previous Day High", pdl COLOURED(200,0,0) STYLE(line,2) AS "Previous Day Low", eqLevel COLOURED(128,128,128) STYLE(dottedline,2) AS "Previous Day EQ", plotO COLOURED(0,110,220) STYLE(dottedline,1) AS "Previous Day Open", plotC COLOURED(230,140,0) STYLE(dottedline,1) AS "Previous Day Close"

The updateonclose modifier guarantees the values come from the last completed daily candle, so nothing repaints during the current session and the lines stay fixed all day, on any intraday timeframe.

For the weekly version (same idea as blackwing’s thread), you only need to change daily to weekly — here it is ready to paste as a second indicator:

//-----------------------------------------------------------//
//PRC_Previous Week High Low EQ
//version = 1
//10.07.2026
//Ivan Gonzalez @ www.prorealcode.com
//Sharing ProRealTime knowledge
//-----------------------------------------------------------//
TIMEFRAME(weekly, updateonclose)
pwh = high[0] // previous week High
pwl = low[0]  // previous week Low
TIMEFRAME(default)


weq = (pwh + pwl) / 2


RETURN pwh COLOURED(0,150,0) STYLE(line,2) AS "Previous Week High", pwl COLOURED(200,0,0) STYLE(line,2) AS "Previous Week Low", weq COLOURED(128,128,128) STYLE(dottedline,2) AS "Previous Week EQ"

A few indicators from the library that do exactly this kind of job, in case you want more complete tools:

• Wolf Trace SMC Key Levels — previous Day / Week / Month highs and lows (PDH, PDL, PWH, PWL, PMH, PML), each level anchored at the exact bar where the extreme was made: https://www.prorealcode.com/prorealtime-indicators/wolf-trace-smc-key-levels/
• Previous OHLC of any candlestick period (yearly / monthly / quarterly / weekly / daily / H4 / H1) — the “missing OHLC” you were looking for: https://www.prorealcode.com/snippet/previous-ohlc-of-candlesticks-period-yearlymonthlyquaterlyweeklydailyh4-and-h1/
• Dynamic Daily Highs & Lows Touch — keeps the last 30 daily highs/lows in memory and reveals each level only when price comes back to touch it, labelled with its age in days: https://www.prorealcode.com/topic/plus-haut-plus-bas-daily-ameliore/

Enjoy the trial!