Have lost ability to upload new images / create new galleries

I’ve been a paid user of Imagely Themes (Ansel), NextGen Pro for 2.5 years for my photography sales site. In general it has worked quite well and I’m pleased with the appearance, load speed and functionality. I’m semi technical but not really a web developer / coder so I’m obviously in over my head, but something has changed within the last month or so which has “broken” my ability to upload new images. I really haven’t changed anything on my end, so I can’t tell if it’s a NextGEN plugin issue, a new wordpress issue, PHP issue etc.

Host: Dreamhost / Dreampress (on the Imagely recommended list)
Wordpress 5.6 / PHP 7.4.3 / NExtGEN 3.5.0

(All below testing performed with all plugins disabled except for NextGen and NextGen Pro. I have also duplicated using Imagely Ansel theme as well as generic 2020 and 2021 themes).

?When I attempt to upload from Lightroom using Imagely plugin, I get “Internal Error ImagelyTask.lua” . I’ve never had reliable results using this plugin so it is not my primary route.
? When I attempt to upload from Lightroom using AlloyPhoto Nextgen plugin (I know this is not Imagely’s tool, but it is more reliable in my experience than the Imagely plugin and has always worked well for me) I get a 32700 parse error.
? When I try to manually upload from PC using Manage Galleries panel I get “Upload Failed, No Images were uploaded” debugging the XHR Response gives the not very descriptive error “{“gallery_name”:”JLeon”,”gallery_id”:111,”error”:”There was a problem uploading the file.”}”
? When I upload images to a gallery directory using FileZilla and then attempt to use Import Folder I get “Unexpected Error Occurred” (Screenshot attached)
? When I upload to a gallery directory using FileZilla and then Scan Folder for New Images from the gallery settings pane, I get the whitescreen error “ImagickException thrown
unable to open pixel cache `/home/wp_USERID/jeffreyjdavis.com/wp-content/gallery/jleon/JeffreyJDavis J Leon Gallery-1.jpg’: No such file or directory @ error/cache.c/OpenPixelCache/3998″ This method DOES add one image to gallery and create a jpg_backup file for said image, but it freezes after the first image load. I tried to do a test, re-exporting from lightroom at lower resolution (1920 x 1280, 500k max jpg size) and this method worked successfully. my normal files are in the range of 6000 x 4000 pxls and may be 5 – 8MB. I sell prints up to 24″ x 36” so need to maintain quality and resolution. but this small image test tells me that core directory and file permissions seem to be functioning.
? I first became aware of the issues when a customer tried to display a previously uploaded and functioning ecommerce gallery got the whitescreen error “ImagickException thrown
cache resources exhausted `/home/wp_4e3ijn/jeffreyjdavis.com/wp-content/gallery/201912-turks-and-caicos-v4/201912.Turks and Caicos -00069.jpg’ @ error/cache.c/OpenPixelCache/3984″

Some of the googling I’ve done and the fact that it seems to work for small images but not for large images keeps making me think it might be related to ImageMagick policy.xml (currently set at default)? Or something in my php.ini? It is just boggling my mind because it used to work smoothly for a couple of years, until it didn’t anymore. Has anyone else run across similar issues ?

[CURRENT IMAGEMAGICK POLICY.XML]
<policy value=”256MiB” name=”memory” domain=”resource”/>
<policy value=”512MiB” name=”map” domain=”resource”/>
<policy value=”16KP” name=”width” domain=”resource”/>
<policy value=”16KP” name=”height” domain=”resource”/>
<policy value=”128MB” name=”area” domain=”resource”/>
<policy value=”1GiB” name=”disk” domain=”resource”/>

The page I need help with: [log in to see the link]