Is anyone getting lots of 'an error occurred' especially during the defensive battles

Only happened to me once, I think.

Error occurred x 4 this week, always when completing a 3 medal. Three times on PC using Firefox, once on iPhone using Puffin.

Very annoying!

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Now, for some advice please. Am currently levelling Alpina (slice), Sandersonia (Hit), Laurentia (Pierce), and Lavender (Magic)

Who is best after these gals out of:

SLICE:
Pentas (double damage to 2 enemies, +1-10% attack for squad based on affection)
Nasturtium (2.3 damage and drain, +10% attack for squad members)
Lupine (1.7 damage all, increased crits for squad)
Waterlily with L2 skill and two equip slots (2.4 damage, medium dodge)
Cherry Sage (2.5 damage, -10% attack for 3 enemies)

HIT:
Bipinna Cosmos (1.5 damage all, +15% Shine Crystal drop rate for squad)
Calla (event girl, 2.4 damage, +15% attack for 2 squad members)
Edelweiss (event girl, 2x damage to 2 enemies), +10% heal squad from Pest Nest Nodes)
Canna (event girl, 2.3 damage, increased critical for 2 squad members)
Adonis (event girl, 2.4 damage, +10% attack for 3 squad members)

PIERCE
Night Phlox with L2 skill and two equip slots (2.3 damage and drain HP, +15% attack for 3 squad members)
Iris (1.4 damage all, extra cannon shot)
Anthurium (2.4 damage, +22% attack for squad on turn 1)
Madonna (1.4 damage to enemies 3 times, +10-30% Attack Power each Solar Blast used)

MAGIC:
Epidendrum (2.3x damage, +1.5 activation self for first turn)
Strawberry Candle with two equip slots (2.5x damage, 2-3 normal nodes turned into solar nodes)
Queen of the Night with two equip slots (x3 damage to 2 enemies, 2x squad healing)
Evening Primrose (x2 damage to 2 enemies, +10% Attack power for squad)
German Iris (2.5x damage, +25% Solar Blast damage)

Thanks for any tips!

Oh, the error only popped for me when I started the map, not when I finished it. Just got a "loading failed" error.

Edit:

Originally Posted by Mindrunner

Still have it, except when I collect a present. Let's hope the next maintenance in about 2 days solves this.

Just got it again several times in a row, both collecting and raiding didn't solve this time. Running a mission fixed it, but it seems this is still going on.

Originally Posted by Maladaptive

Now, for some advice please. Thanks for any tips!

Well, what usually catches my eye in girls is usually team/map utility (Or Solar Blast potential but that's just me.)
So I'd probably go with:

SLICE:
Cherry Sage (2.5 damage, -10% attack for 3 enemies) (Debuff girls are very versatile)

HIT:
Edelweiss (event girl, 2x damage to 2 enemies), +10% heal squad from Pest Nest Nodes) (Healing on Pest + Speed buff to squad)
Adonis (event girl, 2.4 damage, +10% attack for 3 squad members) (Whirlwind/SpiderWeb disable is great)

PIERCE
Anthurium (2.4 damage, +22% attack for squad on turn 1) (Best girl in game. Fact. Also Speed buff utility.)

MAGIC:
Queen of the Night with two equip slots (x3 damage to 2 enemies, 2x squad healing) (Double Squad healing)

All of them have some type of ulterior utility they can bring, but I don't really know which of those might be actually important to you or not.
But you should definitely level up Anthurium.

Now, for some advice please. Am currently levelling Alpina (slice), Sandersonia (Hit), Laurentia (Pierce), and Lavender (Magic)

Who is best after these gals out of:

Slice: Cherry Sage is extremely good and should have priority.
Hit: None of these are amazing, and will all be replaced eventually. Just pick who you like.
Pierce: Night Phlox easily. Her attack is off the chart compared to other gold girls. She will be very important to you in Whale Ship.
Magic: Epidemdrum is the best of this lot. But since your QOTN has two slots, I give her the nod instead.

Thanks to for all the suggestions, really helpful

Hmmm... Wonder what today's new Anniversary gacha will be like. Hopefully something good. If it's not FG based I might end up blowing a few of mine on Stam regens today to make up for lost time and actually grind the Manyu daily map - both those colours fit my new 6 Stars.

Are the 'all FG' daily log in tickets very rare or just mixed in with the first few months as a welcome bonus? I don't think I've seen one in around 5 - 6 months now

Originally Posted by sniddy

Are the 'all FG' daily log in tickets very rare or just mixed in with the first few months as a welcome bonus? I don't think I've seen one in around 5 - 6 months now

You only see that one 2 (maybe 3) times then it's gone for good. A shame really, it would be nice to see it more often, maybe every 10th pane so as not to be too generous but still be often enough to keep people logging in every day.