How to manually set the monitor refresh rate?

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The display settings built into the monitor report the refresh rate and it has been accurate with other systems so I trust its reporting. When running monitor-edid -v I get # Monitor preferred modeline (60.0 Hz vsync, 133.3 kHz hsync, ratio 16/9, 185 dpi) <newline> ModeLine "3840x2160" 533.25 3840 3902 3950 4000 2160 2163 2168 2222 -hsync +vsync in the result. I also get parsing EDID from /sys/class/drm/card0-DP-1/edid so looks like my monitor is on card0-DP-1. Running # monitor-parse-edid -v < /sys/class/drm/card0-DP-1/edid does not seem to give me 60Hz, even after restart.

Also, when running either monitor-edid -v or monitor-parse-edid -v, the output starts with Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/.*? = { <-- HERE / at /usr/bin/monitor-parse-edid line 735.. Maybe this is causing my troubles?

After running the commands a few more times with a few trial-and-error modifications, it seems like my monitor is now reporting 60Hz. I'm not sure exactly what made it work but it's working now based on your answer. Settings in Gnome unfortunately continues to only show 59Hz and 29Hz.

The warning doesn't seem to be a problem at this point, but it might become one in the future.

What is the output of xrandr?

Screen 0: minimum 8 x 8, current 3840 x 2160, maximum 32767 x 32767 <newline> DP1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 530mm x 300mm <newline> 3840x2160 60.00*+ 29.98 <newline> 2560x1440 59.95 <newline> . . . and then it continues to list many resolutions below 3840x2160 with various refresh rates, except none of them have the *+ symbols next to them like 60.00*+ next to 3840x2160.